Add ltree data type to contrib, from Teodor Sigaev and Oleg Bartunov.

23 years ago · 1dedbf2da5
parent 210e64fe08
commit 1dedbf2da5
22 changed files with 14333 additions and 1 deletions
--- a/contrib/Makefile
+++ b/contrib/Makefile
@ -1,4 +1,4 @@
-# $Header: /cvsroot/pgsql/contrib/Makefile,v 1.33 2002/07/30 16:32:20 momjian Exp $
+# $Header: /cvsroot/pgsql/contrib/Makefile,v 1.34 2002/07/30 16:40:34 momjian Exp $

 subdir = contrib
 top_builddir = ..
@ -20,6 +20,7 @@ WANTED_DIRS = \
 		intarray	\
 		isbn_issn	\
 		lo		\
+		ltree		\
 		miscutil	\
 		noupdate	\
 		oid2name	\
--- a/contrib/README
+++ b/contrib/README
@ -95,6 +95,10 @@ lo -
 	Large Object maintenance
 	by Peter Mount <peter@retep.org.uk> 

+ltree -
+	Tree-like data structures
+	by Teodor Sigaev <teodor@stack.net> and Oleg Bartunov <oleg@sai.msu.su>
+
 mSQL-interface -
 	mSQL API translation library
 	by Aldrin Leal <aldrin@americasnet.com>
--- a/contrib/ltree/Makefile
+++ b/contrib/ltree/Makefile
@ -0,0 +1,13 @@
+subdir = contrib/tree
+top_builddir = ../..
+include $(top_builddir)/src/Makefile.global
+
+PG_CPPFLAGS = -DLOWER_NODE
+MODULE_big = ltree
+OBJS = 	ltree_io.o ltree_op.o lquery_op.o _ltree_op.o crc32.o \
+	ltxtquery_io.o ltxtquery_op.o ltree_gist.o _ltree_gist.o
+DATA_built = ltree.sql
+DOCS = README.ltree
+REGRESS = ltree
+
+include $(top_srcdir)/contrib/contrib-global.mk
--- a/contrib/ltree/README.ltree
+++ b/contrib/ltree/README.ltree
@ -0,0 +1,465 @@
+contrib/ltree module
+
+ltree - is a PostgreSQL contrib module which contains implementation of data
+types, indexed access methods and queries for data organized as a tree-like
+structures.
+This module will works for PostgreSQL version 7.3.
+(patch for 7.2 version is provided, see INSTALLATION)
+-------------------------------------------------------------------------------
+All work was done by Teodor Sigaev (teodor@stack.net) and Oleg Bartunov
+(oleg@sai.msu.su). See http://www.sai.msu.su/~megera/postgres/gist for
+additional information. Authors would like to thank Eugeny Rodichev for helpful
+discussions. Comments and bug reports are welcome.
+-------------------------------------------------------------------------------
+
+LEGAL NOTICES: This module is released under BSD license (as PostgreSQL
+itself). This work was done in framework of Russian Scientific Network and
+partially supported by Russian Foundation for Basic Research and Stack Group.
+-------------------------------------------------------------------------------
+
+MOTIVATION
+
+This is a placeholder for introduction to the problem. Hope, people reading
+this document doesn't need it too much :-)
+
+DEFINITIONS
+
+A label of a node is a sequence of one or more words separated by blank
+character '_' and containing letters and digits ( for example, [a-zA-Z0-9] for
+C locale). The length of a label is limited by 256 bytes.
+
+Example: 'Countries', 'Personal_Services'
+
+A label path of a node is a sequence of one or more dot-separated labels
+l1.l2...ln, represents path from root to the node. The length of a label path
+is limited by 65Kb, but size <= 2Kb is preferrable. We consider it's not a
+strict limitation ( maximal size of label path for DMOZ catalogue - http://
+www.dmoz.org, is about 240 bytes !)
+
+Example: 'Top.Countries.Europe.Russia'
+
+We introduce several datatypes:
+
+ltree
+    - is a datatype for label path.
+   
+ltree[]
+    - is a datatype for arrays of ltree.
+   
+lquery
+    - is a path expression that has regular expression in the label path and
+    used for ltree matching. Star symbol (*) is used to specify any number of
+    labels (levels) and could be used at the beginning and the end of lquery,
+    for example, '*.Europe.*'.
+   
+    The following quantifiers are recognized for '*' (like in Perl):
+   
+               {n}    Match exactly n levels
+               {n,}   Match at least n levels
+               {n,m}  Match at least n but not more than m levels
+               {,m}   Match at maximum m levels (eq. to {0,m})
+   
+    It is possible to use several modifiers at the end of a label:
+   
+      
+               @     Do case-insensitive label matching
+               *     Do prefix matching for a label
+               %     Don't account word separator '_' in label matching, that is 
+                     'Russian%' would match 'Russian_nations', but not 'Russian'
+   
+    lquery could contains logical '!' (NOT) at the beginning of the label and '
+    |' (OR) to specify possible alternatives for label matching.
+   
+    Example of lquery:
+   
+    
+                Top.*{0,2}.sport*@.!football|tennis.Russ*|Spain
+                a)  b)     c)      d)               e)
+    
+    A label path should
+      + a) begins from a node with label 'Top'
+      + b) and following zero or 2 labels until
+      + c) a node with label beginning from case-insensitive prefix 'sport'
+      + d) following node with label not matched 'football' or 'tennis' and
+      + e) ends on node with label beginning from 'Russ' or strictly matched
+        'Spain'.
+   
+ltxtquery
+    - is a datatype for label searching (like type 'query' for full text
+    searching, see contrib/tsearch). It's possible to use modifiers @,%,* at
+    the end of word. The meaning of modifiers are the same as for lquery.
+   
+    Example: 'Europe & Russia*@ & !Transportation'
+   
+    Search paths contain words 'Europe' and 'Russia*' (case-insensitive) and
+    not 'Transportation'. Notice, the order of words as they appear in label
+    path is not important !
+
+OPERATIONS
+
+The following operations are defined for type ltree:
+
+<,>,<=,>=,=, <>
+    - have their usual meanings. Comparison is doing in the order of direct
+    tree traversing, children of a node are sorted lexicographic.
+ltree @> ltree
+    - returns TRUE if left argument is an ancestor of right argument (or
+    equal).
+ltree <@ ltree
+    - returns TRUE if left argument is a descendant of right argument (or
+    equal).
+ltree ~ lquery, lquery ~ ltree
+    - return TRUE if node represented by ltree satisfies lquery.
+ltree @ ltxtquery, ltxtquery @ ltree
+    - return TRUE if node represented by ltree satisfies ltxtquery.
+ltree || ltree, ltree || text, text || ltree
+    - return concatenated ltree.
+
+Operations for arrays of ltree (ltree[]):
+
+ltree[] @> ltree, ltree <@ ltree[]
+    - returns TRUE if array ltree[] contains an ancestor of ltree.
+ltree @> ltree[], ltree[] <@ ltree
+    - returns TRUE if array ltree[] contains a descendant of ltree.
+ltree[] ~ lquery, lquery ~ ltree[]
+    - returns TRUE if array ltree[] contains label paths matched lquery.
+ltree[] @ ltxtquery, ltxtquery @ ltree[]
+    - returns TRUE if array ltree[] contains label paths matched ltxtquery
+    (full text search).
+ltree[] ?@> ltree, ltree ?<@ ltree[], ltree[] ?~ lquery, ltree[] ?@ ltxtquery
+    - returns first element of array ltree[] satisfies corresponding condition
+    and NULL in vice versa.
+
+REMARK
+
+Operations <@, @>, @ and ~ have analogues - ^<@, ^@>, ^@, ^~, which doesn't use
+indices !
+
+INDICES
+
+Various indices could be created to speed up execution of operations:
+
+  * B-tree index over ltree:
+    <, <=, =, =>, >
+  * GiST index over ltree:
+    <, <=, =, =>, >, @>, <@, @, ~
+    Example:
+    create index path_gist_idx on test using gist_ltree_ops (path);
+  * GiST index over ltree[]:
+    ltree[]<@ ltree, ltree @> ltree[], @, ~.
+    Example:
+    create index path_gist_idx on test using gist__ltree_ops (array_path);
+    Notices: This index is lossy.
+
+FUNCTIONS
+
+ltree subltree
+      ltree subltree(ltree, start, end) 
+        returns subpath of ltree from start (inclusive) until the end.
+        # select subltree('Top.Child1.Child2',1,2);
+        subltree
+        --------
+        Child1
+ltree subpath
+      ltree subpath(ltree, OFFSET,LEN)
+      ltree subpath(ltree, OFFSET)
+        returns subpath of ltree from OFFSET (inclusive) with length LEN.
+        If OFFSET is negative returns subpath starts that far from the end 
+        of the path.  If LENGTH is omitted, returns everything to the end
+        of the path.  If LENGTH is negative, leaves that many labels off 
+        the end of the path.
+        # select subpath('Top.Child1.Child2',1,2);
+        subpath
+        -------
+        Child1.Child2
+    
+        # select subpath('Top.Child1.Child2',-2,1);
+        subpath 
+        ---------
+        Child1
+int4 nlevel
+      
+       int4 nlevel(ltree) - returns level of the node.
+        # select nlevel('Top.Child1.Child2');
+        nlevel 
+        --------
+          3
+
+Note, that arguments start, end, OFFSET, LEN have meaning of level of the node
+!
+
+INSTALLATION
+
+  cd contrib/ltree
+  make
+  make install
+  make installcheck
+
+for 7.2 one needs to apply patch ( patch < patch.72) before installation !
+
+EXAMPLE OF USAGE
+
+ createdb ltreetest
+ psql ltreetest < /usr/local/pgsql/share/contrib/ltree.sql
+ psql ltreetest < ltreetest.sql
+
+Now, we have a database ltreetest populated with a data describing hierarchy
+shown below:
+
+ 
+                            TOP
+                         /   |  \     
+                 Science Hobbies Collections  
+                     /       |              \
+            Astronomy   Amateurs_Astronomy Pictures
+               /  \                            |
+    Astrophysics  Cosmology                Astronomy
+                                            /  |    \
+                                     Galaxies Stars Astronauts
+
+Inheritance:
+
+ltreetest=# select path from test where path <@ 'Top.Science';
+                path                
+------------------------------------
+ Top.Science
+ Top.Science.Astronomy
+ Top.Science.Astronomy.Astrophysics
+ Top.Science.Astronomy.Cosmology
+(4 rows)
+
+Matching:
+
+ltreetest=# select path from test where path ~ '*.Astronomy.*';
+                     path                      
+-----------------------------------------------
+ Top.Science.Astronomy
+ Top.Science.Astronomy.Astrophysics
+ Top.Science.Astronomy.Cosmology
+ Top.Collections.Pictures.Astronomy
+ Top.Collections.Pictures.Astronomy.Stars
+ Top.Collections.Pictures.Astronomy.Galaxies
+ Top.Collections.Pictures.Astronomy.Astronauts
+(7 rows)
+ltreetest=# select path from test where path ~ '*.!pictures@.*.Astronomy.*';
+                path                
+------------------------------------
+ Top.Science.Astronomy
+ Top.Science.Astronomy.Astrophysics
+ Top.Science.Astronomy.Cosmology
+(3 rows)
+
+Full text search:
+
+ltreetest=# select path from test where path @ 'Astro*% & !pictures@';
+                path                
+------------------------------------
+ Top.Science.Astronomy
+ Top.Science.Astronomy.Astrophysics
+ Top.Science.Astronomy.Cosmology
+ Top.Hobbies.Amateurs_Astronomy
+(4 rows)
+
+ltreetest=# select path from test where path @ 'Astro* & !pictures@';
+                path                
+------------------------------------
+ Top.Science.Astronomy
+ Top.Science.Astronomy.Astrophysics
+ Top.Science.Astronomy.Cosmology
+(3 rows)
+
+Using Functions:
+
+ltreetest=# select subpath(path,0,2)||'Space'||subpath(path,2) from test where path <@ 'Top.Science.Astronomy';
+                 ?column?                 
+------------------------------------------
+ Top.Science.Space.Astronomy
+ Top.Science.Space.Astronomy.Astrophysics
+ Top.Science.Space.Astronomy.Cosmology
+(3 rows)
+We could create SQL-function:
+CREATE FUNCTION ins_label(ltree, int4, text) RETURNS ltree 
+AS 'select subpath($1,0,$2) || $3 || subpath($1,$2);'
+LANGUAGE SQL WITH (ISCACHABLE);
+
+and previous select could be rewritten as:
+
+ltreetest=# select ins_label(path,2,'Space') from test where path <@ 'Top.Science.Astronomy';
+                ins_label                 
+------------------------------------------
+ Top.Science.Space.Astronomy
+ Top.Science.Space.Astronomy.Astrophysics
+ Top.Science.Space.Astronomy.Cosmology
+(3 rows)
+
+Or with another arguments:
+
+CREATE FUNCTION ins_label(ltree, ltree, text) RETURNS ltree
+AS 'select subpath($1,0,nlevel($2)) || $3 || subpath($1,nlevel($2));'
+LANGUAGE SQL WITH (ISCACHABLE);
+
+ltreetest=# select ins_label(path,'Top.Science'::ltree,'Space') from test where path <@ 'Top.Science.Astronomy';
+                ins_label                 
+------------------------------------------
+ Top.Science.Space.Astronomy
+ Top.Science.Space.Astronomy.Astrophysics
+ Top.Science.Space.Astronomy.Cosmology
+(3 rows)
+
+ADDITIONAL DATA
+
+To get more feeling from our ltree module you could download
+dmozltree-eng.sql.gz (about 3Mb tar.gz archive containing 300,274 nodes),
+available from http://www.sai.msu.su/~megera/postgres/gist/ltree/
+dmozltree-eng.sql.gz, which is DMOZ catalogue, prepared for use with ltree.
+Setup your test database (dmoz), load ltree module and issue command:
+
+zcat dmozltree-eng.sql.gz| psql dmoz
+
+Data will be loaded into database dmoz and all indices will be created.
+
+BENCHMARKS
+
+All runs were performed on my IBM ThinkPad T21 (256 MB RAM, 750Mhz) using DMOZ
+data, containing 300,274 nodes (see above for download link). We used some
+basic queries typical for walking through catalog.
+
+QUERIES
+
+  * Q0: Count all rows (sort of base time for comparison)
+    select count(*) from dmoz;
+     count  
+    --------
+     300274
+    (1 row)
+  * Q1: Get direct children (without inheritance)
+    select path from dmoz where path ~ 'Top.Adult.Arts.Animation.*{1}';
+                   path                
+    -----------------------------------
+     Top.Adult.Arts.Animation.Cartoons
+     Top.Adult.Arts.Animation.Anime
+    (2 rows)
+  * Q2: The same as Q1 but with counting of successors
+    select path as parentpath , (select count(*)-1 from dmoz where path <@
+    p.path) as count from dmoz p where path ~ 'Top.Adult.Arts.Animation.*{1}';
+                parentpath             | count 
+    -----------------------------------+-------
+     Top.Adult.Arts.Animation.Cartoons |     2
+     Top.Adult.Arts.Animation.Anime    |    61
+    (2 rows)
+  * Q3: Get all parents
+    select path from dmoz where path @> 'Top.Adult.Arts.Animation' order by
+    path asc;
+               path           
+    --------------------------
+     Top
+     Top.Adult
+     Top.Adult.Arts
+     Top.Adult.Arts.Animation
+    (4 rows)
+  * Q4: Get all parents with counting of children
+    select path, (select count(*)-1 from dmoz where path <@ p.path) as count
+    from dmoz p where path @> 'Top.Adult.Arts.Animation' order by path asc;
+               path           | count  
+    --------------------------+--------
+     Top                      | 300273
+     Top.Adult                |   4913
+     Top.Adult.Arts           |    339
+     Top.Adult.Arts.Animation |     65
+    (4 rows)
+  * Q5: Get all children with levels
+    select path, nlevel(path) - nlevel('Top.Adult.Arts.Animation') as level
+    from dmoz where path ~ 'Top.Adult.Arts.Animation.*{1,2}' order by path asc;
+                          path                      | level 
+    ------------------------------------------------+-------
+     Top.Adult.Arts.Animation.Anime                 |     1
+     Top.Adult.Arts.Animation.Anime.Fan_Works       |     2
+     Top.Adult.Arts.Animation.Anime.Games           |     2
+     Top.Adult.Arts.Animation.Anime.Genres          |     2
+     Top.Adult.Arts.Animation.Anime.Image_Galleries |     2
+     Top.Adult.Arts.Animation.Anime.Multimedia      |     2
+     Top.Adult.Arts.Animation.Anime.Resources       |     2
+     Top.Adult.Arts.Animation.Anime.Titles          |     2
+     Top.Adult.Arts.Animation.Cartoons              |     1
+     Top.Adult.Arts.Animation.Cartoons.AVS          |     2
+     Top.Adult.Arts.Animation.Cartoons.Members      |     2
+    (11 rows)
+
+Timings
+
+---------------------------------------------+
+|Query|Rows|Time (ms) index|Time (ms) no index|
+|-----+----+---------------+------------------|
+|   Q0|   1|             NA|           1453.44|
+|-----+----+---------------+------------------|
+|   Q1|   2|           0.49|           1001.54|
+|-----+----+---------------+------------------|
+|   Q2|   2|           1.48|           3009.39|
+|-----+----+---------------+------------------|
+|   Q3|   4|           0.55|            906.98|
+|-----+----+---------------+------------------|
+|   Q4|   4|       24385.07|           4951.91|
+|-----+----+---------------+------------------|
+|   Q5|  11|           0.85|           1003.23|
+---------------------------------------------+
+Timings without indices were obtained using operations which doesn't use
+indices (see above)
+
+Remarks
+
+We didn't run full-scale tests, also we didn't present (yet) data for
+operations with arrays of ltree (ltree[]) and full text searching. We'll
+appreciate your input. So far, below some (rather obvious) results:
+
+  * Indices does help execution of queries
+  * Q4 performs bad because one needs to read almost all data from the HDD
+
+CHANGES
+
+July 13, 2002
+   Initial release.
+
+TODO
+
+  * Testing on 64-bit platforms. There are several known problems with byte
+    alignment;
+  * Better documentation;
+  * We plan (probably) to improve regular expressions processing using
+    non-deterministic automata;
+  * Some sort of XML support;
+  * Better full text searching;
+
+SOME BACKGROUNDS
+
+The approach we use for ltree is much like one we used in our other GiST based
+contrib modules (intarray, tsearch, tree, btree_gist, rtree_gist). Theoretical
+background is available in papers referenced from our GiST development page
+(http://www.sai.msu.su/~megera/postgres/gist).
+
+A hierarchical data structure (tree) is a set of nodes. Each node has a
+signature (LPS) of a fixed size, which is a hashed label path of that node.
+Traversing a tree we could *certainly* prune branches if
+
+LQS (bitwise AND) LPS != LQS
+
+where LQS is a signature of lquery or ltxtquery, obtained in the same way as
+LPS.
+
+ltree[]:
+For array of ltree LPS is a bitwise OR-ed signatures of *ALL* children
+reachable from that node. Signatures are stored in RD-tree, implemented using
+GiST, which provides indexed access.
+
+ltree:
+For ltree we store LPS in a B-tree, implemented using GiST. Each node entry is
+represented by (left_bound, signature, right_bound), so that we could speedup
+operations <, <=, =, =>, > using left_bound, right_bound and prune branches of
+a tree using signature.
+-------------------------------------------------------------------------------
+We ask people who find the module useful to send us a postcards to:
+Moscow, 119899, Universitetski pr.13, Moscow State University, Sternberg
+Astronomical Institute, Russia
+For: Bartunov O.S.
+and
+Moscow, Bratislavskaya str.23, appt. 18, Russia
+For: Sigaev F.G.
--- a/contrib/ltree/_ltree_gist.c
+++ b/contrib/ltree/_ltree_gist.c
@ -0,0 +1,549 @@
+/*
+ * GiST support for ltree[] 
+ * Teodor Sigaev <teodor@stack.net>
+ */
+
+#include "ltree.h"
+#include "access/gist.h"
+#include "access/rtree.h"
+#include "access/nbtree.h"
+#include "utils/array.h"
+
+#include "crc32.h"
+
+PG_FUNCTION_INFO_V1( _ltree_compress );
+Datum   _ltree_compress(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( _ltree_same );
+Datum   _ltree_same(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( _ltree_union );
+Datum   _ltree_union(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( _ltree_penalty );
+Datum   _ltree_penalty(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( _ltree_picksplit );
+Datum   _ltree_picksplit(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( _ltree_consistent );
+Datum   _ltree_consistent(PG_FUNCTION_ARGS);
+
+#define GETENTRY(vec,pos) ((ltree_gist *) DatumGetPointer(((GISTENTRY *) VARDATA(vec))[(pos)].key))
+#define NEXTVAL(x) ( (ltree*)( (char*)(x) + INTALIGN( VARSIZE(x) ) ) )
+#define SUMBIT(val) (        \
+	GETBITBYTE(val,0) + \
+	GETBITBYTE(val,1) + \
+	GETBITBYTE(val,2) + \
+	GETBITBYTE(val,3) + \
+	GETBITBYTE(val,4) + \
+	GETBITBYTE(val,5) + \
+	GETBITBYTE(val,6) + \
+	GETBITBYTE(val,7)   \
+)
+#define WISH_F(a,b,c) (double)( -(double)(((a)-(b))*((a)-(b))*((a)-(b)))*(c) )
+
+static void
+hashing(BITVECP sign, ltree *t) {
+	int tlen = t->numlevel;
+	ltree_level *cur = LTREE_FIRST(t);
+	int  hash;
+
+	while(tlen > 0) {
+		hash = crc32_sz( cur->name, cur->len );
+		AHASH( sign, hash );
+		cur = LEVEL_NEXT(cur);
+		tlen--;
+	}
+}
+
+Datum   
+_ltree_compress(PG_FUNCTION_ARGS) {
+	GISTENTRY *entry = (GISTENTRY *)PG_GETARG_POINTER(0);
+	GISTENTRY  *retval = entry;
+
+	if ( entry->leafkey ) { /* ltree */
+		ltree_gist	*key;
+		ArrayType	*val = (ArrayType*)DatumGetPointer(PG_DETOAST_DATUM(entry->key));
+		int4 len = LTG_HDRSIZE + ASIGLEN;
+		int num=ArrayGetNItems( ARR_NDIM(val), ARR_DIMS(val) );
+		ltree   *item = (ltree*)ARR_DATA_PTR(val);
+
+		if ( ARR_NDIM(val) != 1 )
+			 elog(ERROR,"Dimension of array != 1");
+
+		key = (ltree_gist*)palloc( len );
+		key->len = len;
+		key->flag = 0;
+
+		MemSet( LTG_SIGN(key), 0, sizeof(ASIGLEN) );
+		while( num>0 ) {
+			hashing(LTG_SIGN(key), item);
+			num--;
+			item = NEXTVAL(item);
+		}
+
+		if ( PointerGetDatum(val) != entry->key )
+			pfree(val);
+
+		retval = (GISTENTRY*)palloc( sizeof(GISTENTRY) );
+		gistentryinit(*retval, PointerGetDatum(key),
+			entry->rel, entry->page,
+			entry->offset, key->len, FALSE);
+	} else {
+		int4 i,len;
+		ltree_gist	*key;
+
+		BITVECP sign = LTG_SIGN(DatumGetPointer( entry->key ) );
+
+		ALOOPBYTE(
+			if ( sign[i] != 0xff )
+				PG_RETURN_POINTER(retval);
+		);
+
+		len = LTG_HDRSIZE; 
+		key = (ltree_gist*)palloc( len );
+		key->len = len;
+		key->flag = LTG_ALLTRUE;
+
+		retval = (GISTENTRY*)palloc( sizeof(GISTENTRY) );
+		gistentryinit(*retval, PointerGetDatum(key),
+			entry->rel, entry->page,
+			entry->offset, key->len, FALSE);
+	}
+	PG_RETURN_POINTER(retval);
+}
+
+Datum   
+_ltree_same(PG_FUNCTION_ARGS) {
+	ltree_gist*	a=(ltree_gist*)PG_GETARG_POINTER(0);
+	ltree_gist*	b=(ltree_gist*)PG_GETARG_POINTER(1);
+	bool *result = (bool *)PG_GETARG_POINTER(2);
+
+	if ( LTG_ISALLTRUE(a) && LTG_ISALLTRUE(b) ) {
+		*result = true;
+	} else if ( LTG_ISALLTRUE(a) ) {
+		*result = false;
+	} else if ( LTG_ISALLTRUE(b) ) {
+		*result = false;
+	} else {
+		int4 i;
+		BITVECP sa=LTG_SIGN(a), sb=LTG_SIGN(b);
+		*result = true;
+		ALOOPBYTE(
+			if ( sa[i] != sb[i] ) {
+				*result = false;
+				break;
+			}
+		);
+	} 
+	PG_RETURN_POINTER(result); 
+}
+
+static int4 
+unionkey( BITVECP sbase, ltree_gist *add ) {
+	int4    i;
+	BITVECP sadd = LTG_SIGN( add );
+
+	if ( LTG_ISALLTRUE(add) )
+		return 1;
+
+	ALOOPBYTE(
+		sbase[i] |= sadd[i];
+	);
+	return 0;
+}
+
+Datum   
+_ltree_union(PG_FUNCTION_ARGS) {
+	bytea *entryvec = (bytea *) PG_GETARG_POINTER(0);
+	int *size = (int *) PG_GETARG_POINTER(1);
+	ABITVEC base;
+	int4 len = (VARSIZE(entryvec) - VARHDRSZ) / sizeof(GISTENTRY);
+	int4 i;
+	int4 flag = 0;
+	ltree_gist	*result;
+
+	MemSet( (void*)base, 0, sizeof(ABITVEC) );
+	for(i=0;i<len;i++) {
+		if ( unionkey( base, GETENTRY(entryvec, i) ) ) {
+			flag = LTG_ALLTRUE;
+			break;
+		}
+	}
+
+	len = LTG_HDRSIZE + ( ( flag & LTG_ALLTRUE ) ? 0 : ASIGLEN );
+	result = (ltree_gist*)palloc( len );
+	*size = result->len = len;
+	result->flag = flag;
+	if ( ! LTG_ISALLTRUE(result) )
+		memcpy((void*)LTG_SIGN(result), (void*)base, sizeof( ABITVEC ) );
+
+	PG_RETURN_POINTER(result);	
+}
+
+static int4
+sizebitvec( BITVECP sign ) {
+	int4 size=0, i;
+	ALOOPBYTE(
+		size += SUMBIT(*(char*)sign);
+		sign = (BITVECP) ( ((char*)sign) + 1 );
+	);
+	return size;
+}
+
+Datum   
+_ltree_penalty(PG_FUNCTION_ARGS) {
+	ltree_gist *origval = (ltree_gist*)DatumGetPointer( ( (GISTENTRY *)PG_GETARG_POINTER(0) )->key );
+	ltree_gist *newval  = (ltree_gist*)DatumGetPointer( ( (GISTENTRY *)PG_GETARG_POINTER(1) )->key );
+	float  *penalty = (float *)    PG_GETARG_POINTER(2);
+	BITVECP orig = LTG_SIGN(origval);
+
+	if ( LTG_ISALLTRUE(origval) ) {
+		*penalty = 0.0;
+		PG_RETURN_POINTER( penalty );
+	}
+
+	if ( LTG_ISALLTRUE(newval) ) {
+		*penalty = (float) (ASIGLENBIT - sizebitvec( orig ) );
+	} else {
+		unsigned char valtmp;
+		BITVECP nval = LTG_SIGN(newval);
+		int4 i, unionsize=0;
+
+		ALOOPBYTE(
+			valtmp = nval[i] | orig[i];
+			unionsize += SUMBIT(valtmp) - SUMBIT(orig[i]);
+		);
+		*penalty = (float)unionsize;
+	}
+	PG_RETURN_POINTER( penalty );
+}
+
+typedef struct {
+	OffsetNumber    pos;
+	int4           cost;
+} SPLITCOST;
+
+static int
+comparecost( const void *a, const void *b ) {
+	return ((SPLITCOST*)a)->cost - ((SPLITCOST*)b)->cost;
+}
+
+Datum   
+_ltree_picksplit(PG_FUNCTION_ARGS) {
+	bytea *entryvec = (bytea*) PG_GETARG_POINTER(0);
+	GIST_SPLITVEC *v = (GIST_SPLITVEC*) PG_GETARG_POINTER(1);
+	OffsetNumber k,j;
+	ltree_gist	*datum_l, *datum_r;
+	ABITVEC	union_l, union_r;
+	bool            firsttime = true;
+	int4    size_alpha,size_beta,sizeu,sizei;
+	int4    size_waste, waste = 0.0;
+	int4    size_l, size_r;
+	int4    nbytes;
+	OffsetNumber seed_1=0, seed_2=0;
+	OffsetNumber    *left, *right;
+	OffsetNumber maxoff;
+	BITVECP ptra, ptrb, ptrc;
+	int i;
+	unsigned char    valtmp;
+	SPLITCOST       *costvector;
+	ltree_gist	*_k, *_j;
+
+	maxoff = ((VARSIZE(entryvec) - VARHDRSZ) / sizeof(GISTENTRY)) - 2;
+	nbytes = (maxoff + 2) * sizeof(OffsetNumber);
+	v->spl_left = (OffsetNumber *) palloc(nbytes);
+	v->spl_right = (OffsetNumber *) palloc(nbytes);
+
+	for (k = FirstOffsetNumber; k < maxoff; k = OffsetNumberNext(k)) {
+		_k = GETENTRY(entryvec,k); 
+		for (j = OffsetNumberNext(k); j <= maxoff; j = OffsetNumberNext(j)) {
+			_j = GETENTRY(entryvec,j);
+			if ( LTG_ISALLTRUE(_k) || LTG_ISALLTRUE(_j) ) {
+				sizeu = ASIGLENBIT;
+				if ( LTG_ISALLTRUE(_k) && LTG_ISALLTRUE(_j) )
+					sizei = ASIGLENBIT;
+				else
+					sizei = ( LTG_ISALLTRUE(_k) ) ? 
+						sizebitvec( LTG_SIGN(_j) ) : sizebitvec( LTG_SIGN(_k) ); 
+			} else {
+				sizeu = sizei = 0;
+				ptra = LTG_SIGN(_j);
+				ptrb = LTG_SIGN(_k);
+				/* critical section for bench !!! */
+
+#define COUNT(pos) do { \
+	if ( GETBITBYTE(*(char*)ptra,pos) ) { \
+		sizeu++; \
+		if ( GETBITBYTE(*(char*)ptrb, pos) ) \
+			sizei++; \
+	} else if ( GETBITBYTE(*(char*)ptrb, pos) ) \
+		sizeu++; \
+} while(0)
+
+				ALOOPBYTE(
+					COUNT(0);
+					COUNT(1);
+					COUNT(2);
+					COUNT(3);
+					COUNT(4);
+					COUNT(5);
+					COUNT(6);
+					COUNT(7);
+					ptra = (BITVECP) ( ((char*)ptra) + 1 );
+					ptrb = (BITVECP) ( ((char*)ptrb) + 1 );
+				);
+			}
+			size_waste = sizeu - sizei;
+			if (size_waste > waste || firsttime) {
+				waste = size_waste;
+				seed_1 = k;
+				seed_2 = j;
+				firsttime = false;
+			}
+		}
+	}
+
+	left = v->spl_left;
+	v->spl_nleft = 0;
+	right = v->spl_right;
+	v->spl_nright = 0;
+
+	if ( seed_1 == 0 || seed_2 == 0 ) {
+		seed_1 = 1;
+		seed_2 = 2;
+	}
+
+	/* form initial .. */
+	if ( LTG_ISALLTRUE(GETENTRY(entryvec,seed_1)) ) {
+		datum_l = (ltree_gist*)palloc( LTG_HDRSIZE );
+		datum_l->len = LTG_HDRSIZE; datum_l->flag = LTG_ALLTRUE;
+		size_l = ASIGLENBIT;
+	} else {
+		datum_l = (ltree_gist*)palloc( LTG_HDRSIZE + ASIGLEN );
+		datum_l->len = LTG_HDRSIZE + ASIGLEN; datum_l->flag = 0;
+		memcpy((void*)LTG_SIGN(datum_l), (void*)LTG_SIGN(GETENTRY(entryvec,seed_1)), sizeof(ABITVEC));
+		size_l = sizebitvec( LTG_SIGN(datum_l) );
+	}
+	if ( LTG_ISALLTRUE(GETENTRY(entryvec,seed_2)) ) {
+		datum_r = (ltree_gist*)palloc( LTG_HDRSIZE );
+		datum_r->len = LTG_HDRSIZE; datum_r->flag = LTG_ALLTRUE;
+		size_r = ASIGLENBIT;
+	} else {
+		datum_r = (ltree_gist*)palloc( LTG_HDRSIZE + ASIGLEN );
+		datum_r->len = LTG_HDRSIZE + ASIGLEN; datum_r->flag = 0;
+		memcpy((void*)LTG_SIGN(datum_r), (void*)LTG_SIGN(GETENTRY(entryvec,seed_2)), sizeof(ABITVEC));
+		size_r = sizebitvec( LTG_SIGN(datum_r) );
+	}
+
+	maxoff = OffsetNumberNext(maxoff);
+	/* sort before ... */
+	costvector=(SPLITCOST*)palloc( sizeof(SPLITCOST)*maxoff );
+	for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j)) {
+		costvector[j-1].pos = j;
+		_j = GETENTRY(entryvec,j);
+		if ( LTG_ISALLTRUE(_j) ) {
+			size_alpha = ASIGLENBIT - size_l;
+			size_beta  = ASIGLENBIT - size_r;
+		} else {
+			ptra = LTG_SIGN( datum_l );
+			ptrb = LTG_SIGN( datum_r );
+			ptrc = LTG_SIGN( _j );
+			size_beta = size_alpha = 0;
+			if ( LTG_ISALLTRUE(datum_l) ) {
+				if ( !LTG_ISALLTRUE(datum_r) ) {
+					ALOOPBIT(
+						if ( GETBIT(ptrc,i) && ! GETBIT(ptrb,i) )
+							size_beta++;
+					);
+				}
+			} else if ( LTG_ISALLTRUE(datum_r) ) {
+				if ( !LTG_ISALLTRUE(datum_l) ) {
+					ALOOPBIT(
+						 if ( GETBIT(ptrc,i) && ! GETBIT(ptra,i) )
+							size_alpha++;
+					);
+				}
+			} else {
+				ALOOPBIT(
+					if ( GETBIT(ptrc,i) && ! GETBIT(ptra,i) )
+						size_alpha++;
+					if ( GETBIT(ptrc,i) && ! GETBIT(ptrb,i) )
+						size_beta++;
+				);
+			}
+		}
+		costvector[j-1].cost = abs( size_alpha - size_beta );
+	}
+	qsort( (void*)costvector, maxoff, sizeof(SPLITCOST), comparecost );
+
+	for (k = 0; k < maxoff; k++) {
+		j = costvector[k].pos;
+		_j = GETENTRY(entryvec,j);
+		if ( j == seed_1 ) {
+			*left++ = j;
+			v->spl_nleft++;
+			continue;
+		} else if ( j == seed_2 ) {
+			*right++ = j;
+			v->spl_nright++;
+			continue;
+		}
+
+		if ( LTG_ISALLTRUE(datum_l) || LTG_ISALLTRUE(_j) ) {
+			size_alpha = ASIGLENBIT;
+		} else {
+			ptra = LTG_SIGN(_j);
+			ptrb = LTG_SIGN(datum_l);
+			size_alpha = 0;
+			ALOOPBYTE(
+				valtmp = union_l[i] = ptra[i] | ptrb[i];
+				size_alpha += SUMBIT( valtmp );
+			);
+		}
+
+		if ( LTG_ISALLTRUE(datum_r) || LTG_ISALLTRUE(_j) ) {
+			size_beta = ASIGLENBIT;
+		} else {
+			ptra = LTG_SIGN(_j);
+			ptrb = LTG_SIGN(datum_r);
+			size_beta = 0;
+			ALOOPBYTE(
+				valtmp = union_r[i] = ptra[i] | ptrb[i];
+				size_beta += SUMBIT( valtmp );
+			);
+		}
+
+		if (size_alpha - size_l < size_beta - size_r + WISH_F(v->spl_nleft, v->spl_nright, 0.1)) {
+			if ( ! LTG_ISALLTRUE( datum_l ) ) {
+				if ( size_alpha == ASIGLENBIT ) {
+					if ( size_alpha != size_l )
+						MemSet( (void*)LTG_SIGN(datum_l),0xff, sizeof(ABITVEC));
+				} else
+					memcpy( (void*)LTG_SIGN(datum_l), (void*)union_l, sizeof(ABITVEC) );
+			}
+			size_l = size_alpha;
+			*left++ = j;
+			v->spl_nleft++;
+		} else {
+			if ( ! LTG_ISALLTRUE( datum_r ) ) {
+				if ( size_beta == ASIGLENBIT ) {
+					if ( size_beta != size_r )
+						MemSet( (void*)LTG_SIGN(datum_r),0xff, sizeof(ABITVEC));
+				} else
+					memcpy( (void*)LTG_SIGN(datum_r), (void*)union_r, sizeof(ABITVEC) );
+			}
+			size_r = size_beta;
+			*right++ = j;
+			v->spl_nright++;
+		}
+	}
+
+	*right = *left = FirstOffsetNumber;
+	pfree(costvector);
+
+	v->spl_ldatum = PointerGetDatum(datum_l);
+	v->spl_rdatum = PointerGetDatum(datum_r);
+
+	PG_RETURN_POINTER( v );
+}
+
+static bool
+gist_te(ltree_gist *key, ltree* query) {
+	ltree_level    *curq = LTREE_FIRST(query);
+	BITVECP sign = LTG_SIGN(key);
+	int     qlen = query->numlevel;
+	unsigned int hv;
+
+	if ( LTG_ISALLTRUE(key) )
+		return true;
+
+	while( qlen>0 ) {
+		hv = crc32_sz(curq->name,curq->len);
+		if ( ! GETBIT( sign, AHASHVAL(hv) ) )
+			return false; 
+		curq = LEVEL_NEXT(curq);
+		qlen--;
+	}
+
+	return true;
+}
+
+static bool
+checkcondition_bit(void *checkval, ITEM* val ) {
+	return ( FLG_CANLOOKSIGN(val->flag) ) ? GETBIT( checkval, AHASHVAL( val->val ) ) : true;
+}
+
+static bool
+gist_qtxt(ltree_gist *key, ltxtquery* query) {
+	if ( LTG_ISALLTRUE(key) )
+		return true;
+            
+	return execute(
+		GETQUERY(query),
+		(void*)LTG_SIGN(key), false,
+		checkcondition_bit
+	);
+}
+
+static bool
+gist_qe(ltree_gist *key, lquery* query) {
+	lquery_level    *curq = LQUERY_FIRST(query);
+	BITVECP sign = LTG_SIGN(key);
+	int     qlen = query->numlevel;
+					 
+	if ( LTG_ISALLTRUE(key) )
+		return true;
+			    
+	while( qlen>0 ) {
+		if ( curq->numvar && LQL_CANLOOKSIGN(curq) ) {
+			bool isexist=false;
+			int vlen = curq->numvar;
+			lquery_variant *curv = LQL_FIRST(curq);
+			while( vlen>0 ) {
+				if ( GETBIT( sign, AHASHVAL( curv->val ) ) ) {
+					isexist=true;
+					break;
+				}
+				curv = LVAR_NEXT(curv);
+				vlen--;
+			}
+			if ( !isexist )
+				return false;
+		}
+ 
+		curq = LQL_NEXT(curq);
+		qlen--;
+	}
+
+	return true;
+}
+
+
+Datum   
+_ltree_consistent(PG_FUNCTION_ARGS) {
+	GISTENTRY *entry = (GISTENTRY*)PG_GETARG_POINTER(0);
+	char *query = (char*)DatumGetPointer( PG_DETOAST_DATUM(PG_GETARG_DATUM(1)) );
+	ltree_gist *key = (ltree_gist*)DatumGetPointer( entry->key );
+	StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
+	bool res = false;
+
+#ifndef assert_enabled 
+#define assert_enabled 0
+#endif
+	
+	switch( strategy ) {
+		case 10:
+		case 11:
+			res =  gist_te(key, (ltree*)query);
+			break;
+		case 12:
+		case 13:
+			res =  gist_qe(key, (lquery*)query);
+			break; 
+		case 14:
+		case 15:
+			res = gist_qtxt(key, (ltxtquery*)query);
+			break;	
+		default:
+			elog(ERROR,"Unknown StrategyNumber: %d", strategy);
+	}
+	PG_RETURN_BOOL(res);
+}
+
--- a/contrib/ltree/_ltree_op.c
+++ b/contrib/ltree/_ltree_op.c
@ -0,0 +1,212 @@
+/*
+ * op function for ltree[] 
+ * Teodor Sigaev <teodor@stack.net>
+ */
+
+#include "ltree.h"
+#include <ctype.h>
+#include "utils/array.h"
+
+PG_FUNCTION_INFO_V1(_ltree_isparent);
+PG_FUNCTION_INFO_V1(_ltree_r_isparent);
+PG_FUNCTION_INFO_V1(_ltree_risparent);
+PG_FUNCTION_INFO_V1(_ltree_r_risparent);
+PG_FUNCTION_INFO_V1(_ltq_regex);
+PG_FUNCTION_INFO_V1(_ltq_rregex);
+PG_FUNCTION_INFO_V1(_ltxtq_exec);
+PG_FUNCTION_INFO_V1(_ltxtq_rexec);
+
+Datum _ltree_r_isparent(PG_FUNCTION_ARGS);
+Datum _ltree_r_risparent(PG_FUNCTION_ARGS);
+
+PG_FUNCTION_INFO_V1(_ltree_extract_isparent);
+PG_FUNCTION_INFO_V1(_ltree_extract_risparent);
+PG_FUNCTION_INFO_V1(_ltq_extract_regex);
+PG_FUNCTION_INFO_V1(_ltxtq_extract_exec);
+Datum _ltree_extract_isparent(PG_FUNCTION_ARGS);
+Datum _ltree_extract_risparent(PG_FUNCTION_ARGS);
+Datum _ltq_extract_regex(PG_FUNCTION_ARGS);
+Datum _ltxtq_extract_exec(PG_FUNCTION_ARGS);
+
+
+typedef Datum (*PGCALL2)(PG_FUNCTION_ARGS);
+#define NEXTVAL(x) ( (ltree*)( (char*)(x) + INTALIGN( VARSIZE(x) ) ) )
+
+static bool
+array_iterator( ArrayType *la, PGCALL2 callback, void* param, ltree ** found) {
+	int num=ArrayGetNItems( ARR_NDIM(la), ARR_DIMS(la));
+	ltree	*item = (ltree*)ARR_DATA_PTR(la);
+
+	if ( ARR_NDIM(la) !=1 )
+		elog(ERROR,"Dimension of array != 1");
+
+	if ( found )
+		*found=NULL;
+	while( num>0 ) {
+		if ( DatumGetBool( DirectFunctionCall2( callback, 
+			PointerGetDatum(item), PointerGetDatum(param) ) ) ) {
+
+			if ( found )
+				*found = item;
+			return true;
+		}
+		num--;
+		item = NEXTVAL(item); 
+	}
+
+	return false;
+}
+
+Datum
+_ltree_isparent(PG_FUNCTION_ARGS) {
+	ArrayType	*la = (ArrayType *)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ltree		*query = PG_GETARG_LTREE(1);
+	bool res = array_iterator( la, ltree_isparent, (void*)query, NULL );
+	PG_FREE_IF_COPY(la,0);
+	PG_FREE_IF_COPY(query,1);
+	PG_RETURN_BOOL(res);
+}
+
+Datum
+_ltree_r_isparent(PG_FUNCTION_ARGS) {
+	PG_RETURN_DATUM( DirectFunctionCall2( _ltree_isparent,
+		PG_GETARG_DATUM(1),
+		PG_GETARG_DATUM(0)
+	) );
+}
+
+Datum
+_ltree_risparent(PG_FUNCTION_ARGS) {
+	ArrayType	*la = (ArrayType *)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ltree		*query = PG_GETARG_LTREE(1);
+	bool res = array_iterator( la, ltree_risparent, (void*)query, NULL );
+	PG_FREE_IF_COPY(la,0);
+	PG_FREE_IF_COPY(query,1);
+	PG_RETURN_BOOL(res);
+}
+
+Datum
+_ltree_r_risparent(PG_FUNCTION_ARGS) {
+	PG_RETURN_DATUM( DirectFunctionCall2( _ltree_risparent,
+		PG_GETARG_DATUM(1),
+		PG_GETARG_DATUM(0)
+	) );
+}
+
+Datum
+_ltq_regex(PG_FUNCTION_ARGS) {
+	ArrayType	*la = (ArrayType *)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	lquery		*query = PG_GETARG_LQUERY(1);
+	bool res = array_iterator( la, ltq_regex, (void*)query, NULL );
+	PG_FREE_IF_COPY(la,0);
+	PG_FREE_IF_COPY(query,1);
+	PG_RETURN_BOOL(res);
+}
+
+Datum
+_ltq_rregex(PG_FUNCTION_ARGS) {
+	PG_RETURN_DATUM( DirectFunctionCall2( _ltq_regex,
+		PG_GETARG_DATUM(1),
+		PG_GETARG_DATUM(0)
+	) );
+}
+
+Datum   
+_ltxtq_exec(PG_FUNCTION_ARGS) {
+	ArrayType	*la = (ArrayType *)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ltxtquery	*query = PG_GETARG_LTXTQUERY(1);
+	bool res = array_iterator( la, ltxtq_exec, (void*)query, NULL );
+	PG_FREE_IF_COPY(la,0);
+	PG_FREE_IF_COPY(query,1);
+	PG_RETURN_BOOL(res);
+}
+
+Datum
+_ltxtq_rexec(PG_FUNCTION_ARGS) {
+	PG_RETURN_DATUM( DirectFunctionCall2( _ltxtq_exec,
+		PG_GETARG_DATUM(1),
+		PG_GETARG_DATUM(0)
+	) );
+}
+
+
+Datum 
+_ltree_extract_isparent(PG_FUNCTION_ARGS) {
+	ArrayType	*la = (ArrayType *)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ltree		*query = PG_GETARG_LTREE(1);
+	ltree		*found,*item;
+
+	if ( !array_iterator( la, ltree_isparent, (void*)query, &found )  ) {
+		PG_FREE_IF_COPY(la,0);
+		PG_FREE_IF_COPY(query,1);
+		PG_RETURN_NULL();
+	}
+
+	item = (ltree*)palloc( found->len );
+	memcpy( item, found, found->len );	
+	
+	PG_FREE_IF_COPY(la,0);
+	PG_FREE_IF_COPY(query,1);
+	PG_RETURN_POINTER(item);
+}
+
+Datum 
+_ltree_extract_risparent(PG_FUNCTION_ARGS) {
+	ArrayType	*la = (ArrayType *)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ltree		*query = PG_GETARG_LTREE(1);
+	ltree		*found,*item;
+
+	if ( !array_iterator( la, ltree_risparent, (void*)query, &found )  ) {
+		PG_FREE_IF_COPY(la,0);
+		PG_FREE_IF_COPY(query,1);
+		PG_RETURN_NULL();
+	}
+
+	item = (ltree*)palloc( found->len );
+	memcpy( item, found, found->len );	
+	
+	PG_FREE_IF_COPY(la,0);
+	PG_FREE_IF_COPY(query,1);
+	PG_RETURN_POINTER(item);
+}
+
+Datum 
+_ltq_extract_regex(PG_FUNCTION_ARGS) {
+	ArrayType	*la = (ArrayType *)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	lquery		*query = PG_GETARG_LQUERY(1);
+	ltree		*found,*item;
+
+	if ( !array_iterator( la, ltq_regex, (void*)query, &found )  ) {
+		PG_FREE_IF_COPY(la,0);
+		PG_FREE_IF_COPY(query,1);
+		PG_RETURN_NULL();
+	}
+
+	item = (ltree*)palloc( found->len );
+	memcpy( item, found, found->len );	
+	
+	PG_FREE_IF_COPY(la,0);
+	PG_FREE_IF_COPY(query,1);
+	PG_RETURN_POINTER(item);
+}
+
+Datum 
+_ltxtq_extract_exec(PG_FUNCTION_ARGS) {
+	ArrayType	*la = (ArrayType *)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ltxtquery	*query = PG_GETARG_LTXTQUERY(1);
+	ltree		*found,*item;
+
+	if ( !array_iterator( la, ltxtq_exec, (void*)query, &found )  ) {
+		PG_FREE_IF_COPY(la,0);
+		PG_FREE_IF_COPY(query,1);
+		PG_RETURN_NULL();
+	}
+
+	item = (ltree*)palloc( found->len );
+	memcpy( item, found, found->len );	
+	
+	PG_FREE_IF_COPY(la,0);
+	PG_FREE_IF_COPY(query,1);
+	PG_RETURN_POINTER(item);
+}
+
--- a/contrib/ltree/crc32.c
+++ b/contrib/ltree/crc32.c
@ -0,0 +1,110 @@
+/* Both POSIX and CRC32 checksums */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <sys/types.h>
+
+#ifdef LOWER_NODE
+#include <ctype.h>
+#define TOLOWER(x)	tolower(x)
+#else
+#define TOLOWER(x)	(x)
+#endif
+
+#include "crc32.h"
+
+/*
+ * This code implements the AUTODIN II polynomial
+ * The variable corresponding to the macro argument "crc" should
+ * be an unsigned long.
+ * Oroginal code  by Spencer Garrett <srg@quick.com>
+ */
+
+#define _CRC32_(crc, ch)	 (crc = (crc >> 8) ^ crc32tab[(crc ^ (ch)) & 0xff])
+
+/* generated using the AUTODIN II polynomial
+ *	x^32 + x^26 + x^23 + x^22 + x^16 +
+ *	x^12 + x^11 + x^10 + x^8 + x^7 + x^5 + x^4 + x^2 + x^1 + 1
+ */
+
+static const unsigned int crc32tab[256] = {
+	0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
+	0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
+	0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
+	0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
+	0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
+	0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
+	0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
+	0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
+	0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
+	0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
+	0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
+	0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
+	0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
+	0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
+	0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
+	0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
+	0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
+	0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
+	0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
+	0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
+	0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
+	0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
+	0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
+	0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
+	0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
+	0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
+	0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
+	0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
+	0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
+	0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
+	0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
+	0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
+	0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
+	0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
+	0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
+	0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
+	0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
+	0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
+	0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
+	0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
+	0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
+	0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
+	0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
+	0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
+	0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
+	0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
+	0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
+	0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
+	0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
+	0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
+	0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
+	0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
+	0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
+	0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
+	0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
+	0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
+	0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
+	0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
+	0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
+	0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
+	0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
+	0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
+	0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
+	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
+};
+
+unsigned int
+crc32_sz(char *buf, int size)
+{
+	unsigned int crc = ~0;
+	char	   *p;
+	int			len,
+				nr;
+
+	len = 0;
+	nr = size;
+	for (len += nr, p = buf; nr--; ++p)
+		_CRC32_(crc, TOLOWER(*p));
+	return ~crc;
+}
--- a/contrib/ltree/crc32.h
+++ b/contrib/ltree/crc32.h
@ -0,0 +1,10 @@
+#ifndef _CRC32_H
+#define _CRC32_H
+
+/* Returns crc32 of data block */
+extern unsigned int crc32_sz(char *buf, int size);
+
+/* Returns crc32 of null-terminated string */
+#define crc32(buf) crc32_sz((buf),strlen(buf))
+
+#endif
--- a/contrib/ltree/data/_ltree.data
+++ b/contrib/ltree/data/_ltree.data
--- a/contrib/ltree/data/ltree.data
+++ b/contrib/ltree/data/ltree.data
--- a/contrib/ltree/expected/ltree.out
+++ b/contrib/ltree/expected/ltree.out
--- a/contrib/ltree/lquery_op.c
+++ b/contrib/ltree/lquery_op.c
@ -0,0 +1,240 @@
+/*
+ * op function for ltree and lquery 
+ * Teodor Sigaev <teodor@stack.net>
+ */
+
+#include "ltree.h"
+#include <ctype.h>
+
+PG_FUNCTION_INFO_V1(ltq_regex);
+PG_FUNCTION_INFO_V1(ltq_rregex);
+
+typedef struct {
+	lquery_level	*q;
+	int		nq;
+	ltree_level	*t;
+	int		nt;
+	int		posq;
+	int		post;
+} FieldNot;
+
+static char *
+getlexem(char *start, char *end, int *len) {
+	char *ptr;
+	
+	while( start<end && *start == '_' )
+		start++;
+
+	ptr = start;
+	if ( ptr == end )
+		return NULL;
+
+	while( ptr < end && *ptr != '_') 
+		ptr++;
+
+	*len = ptr - start;
+	return start;
+}
+
+bool
+compare_subnode( ltree_level *t, char *qn, int len, int (*cmpptr)(const char *,const char *,size_t), bool anyend ) {
+	char *endt = t->name + t->len;
+	char *endq = qn + len;
+	char *tn;
+	int lent,lenq;
+	bool	isok;
+
+	while( (qn=getlexem(qn,endq,&lenq)) != NULL ) {
+		tn=t->name;
+		isok = false;
+		while( (tn=getlexem(tn,endt,&lent)) != NULL ) {
+			if ( 
+				(
+					lent == lenq ||
+					( lent > lenq && anyend )
+				) &&
+				(*cmpptr)(qn,tn,lenq) == 0 ) {
+		
+				isok = true;	
+				break;
+			}
+			tn += lent;
+		}
+
+		if ( !isok )
+			return false;
+		qn += lenq;
+	}
+
+	return true;
+}
+
+static bool
+checkLevel( lquery_level *curq, ltree_level *curt ) {
+	int (*cmpptr)(const char *,const char *,size_t);
+	lquery_variant *curvar = LQL_FIRST(curq);
+	int i;
+	
+	for(i=0;i<curq->numvar;i++) {
+		cmpptr = ( curvar->flag & LVAR_INCASE ) ? strncasecmp : strncmp;
+
+		if ( curvar->flag & LVAR_SUBLEXEM ) {
+			if ( compare_subnode(curt, curvar->name, curvar->len, cmpptr, (curvar->flag & LVAR_ANYEND) ) )
+				return true;
+		} else if ( 
+			( 
+				curvar->len == curt->len || 
+				( curt->len > curvar->len && (curvar->flag & LVAR_ANYEND) )  
+			) && 
+			(*cmpptr)( curvar->name, curt->name, curvar->len) == 0 ) {
+
+			return true;
+		}
+		curvar = LVAR_NEXT(curvar); 
+	}
+	return false;
+}
+
+/*
+void
+printFieldNot(FieldNot *fn ) {
+	while(fn->q) {
+		elog(NOTICE,"posQ:%d lenQ:%d posT:%d lenT:%d", fn->posq,fn->nq,fn->post,fn->nt);
+		fn++;
+	}
+} 
+*/
+
+static bool
+checkCond( lquery_level *curq, int query_numlevel, ltree_level *curt, int tree_numlevel, FieldNot *ptr ) {
+	uint32 low_pos=0,high_pos=0,cur_tpos=0;
+	int tlen = tree_numlevel, qlen = query_numlevel;
+	int isok;
+	lquery_level *prevq=NULL;
+	ltree_level  *prevt=NULL;
+
+	while( tlen >0 && qlen>0 ) {
+		if ( curq->numvar ) {
+			prevt = curt;
+			while ( cur_tpos < low_pos ) {
+				curt = LEVEL_NEXT(curt);
+				tlen--;
+				cur_tpos++;
+				if ( tlen==0 )
+					return false;
+				if ( ptr && ptr->q )
+					ptr->nt++;
+			}
+			
+			if ( ptr && curq->flag & LQL_NOT ) {
+				if ( !(prevq && prevq->numvar == 0) )
+					prevq = curq;
+				if ( ptr->q == NULL ) {
+					ptr->t = prevt;
+					ptr->q = prevq;
+					ptr->nt=1;
+					ptr->nq=1 + ( (prevq==curq) ? 0 : 1 );
+					ptr->posq = query_numlevel - qlen - ( (prevq==curq) ? 0 : 1 ); 
+					ptr->post = cur_tpos;
+				} else {
+					ptr->nt++;
+					ptr->nq++;
+				}
+
+				if ( qlen == 1 && ptr->q->numvar==0 )
+					ptr->nt = tree_numlevel - ptr->post; 
+				curt = LEVEL_NEXT(curt);
+				tlen--;
+				cur_tpos++;
+				if ( high_pos < cur_tpos )
+					high_pos++;
+			} else { 
+				isok = false;
+				while( cur_tpos <= high_pos && tlen > 0 && !isok) {
+					isok = checkLevel(curq, curt);
+					curt = LEVEL_NEXT(curt);
+					tlen--;
+					cur_tpos++;
+					if ( !isok && ptr )
+						ptr->nt++;
+				}
+				if ( !isok )
+					return false;
+
+				if (ptr && ptr->q) {
+					if ( checkCond(ptr->q,ptr->nq,ptr->t,ptr->nt,NULL) )
+						return false;
+					ptr->q = NULL;
+				}
+				low_pos=cur_tpos; high_pos=cur_tpos;
+			}
+		} else {
+			low_pos = cur_tpos + curq->low;
+			high_pos = cur_tpos + curq->high;
+			if ( ptr && ptr->q ) {
+				ptr->nq++;
+				if ( qlen==1 )
+					ptr->nt = tree_numlevel - ptr->post;
+			}
+		}
+
+		prevq = curq;
+		curq = LQL_NEXT(curq);
+		qlen--;
+	}	
+
+	if ( low_pos > tree_numlevel || tree_numlevel > high_pos )
+		return false;
+
+	while( qlen>0 ) {
+		if ( curq->numvar ) {
+			if ( ! (curq->flag & LQL_NOT) )
+				return false;
+		} else {
+			low_pos = cur_tpos + curq->low;
+			high_pos = cur_tpos + curq->high;
+		}
+
+		curq = LQL_NEXT(curq);
+		qlen--;
+	}
+
+	if ( low_pos > tree_numlevel || tree_numlevel > high_pos )
+		return false;
+	
+	if ( ptr && ptr->q && checkCond(ptr->q,ptr->nq,ptr->t,ptr->nt,NULL) )
+		return false;
+	
+	return true;
+}
+
+Datum
+ltq_regex(PG_FUNCTION_ARGS) {
+	ltree *tree = PG_GETARG_LTREE(0);
+	lquery *query = PG_GETARG_LQUERY(1);
+	bool res= false;
+
+	if ( query->flag & LQUERY_HASNOT ) {
+		FieldNot	fn;
+
+		fn.q=NULL;
+
+		res = checkCond( LQUERY_FIRST(query), query->numlevel, 
+			LTREE_FIRST(tree), tree->numlevel, &fn );
+	} else {
+		res = checkCond( LQUERY_FIRST(query), query->numlevel, 
+			LTREE_FIRST(tree), tree->numlevel, NULL ); 
+	}
+
+        PG_FREE_IF_COPY(tree,0);
+        PG_FREE_IF_COPY(query,1);
+        PG_RETURN_BOOL(res);
+}
+
+Datum 
+ltq_rregex(PG_FUNCTION_ARGS) {
+	PG_RETURN_DATUM( DirectFunctionCall2( ltq_regex,
+		PG_GETARG_DATUM(1),
+		PG_GETARG_DATUM(0)
+	) );
+}
--- a/contrib/ltree/ltree.h
+++ b/contrib/ltree/ltree.h
@ -0,0 +1,251 @@
+#ifndef __LTREE_H__
+#define __LTREE_H__
+
+#include "postgres.h"
+#include "utils/elog.h"
+#include "utils/palloc.h"
+#include "utils/builtins.h"
+
+typedef struct {
+	uint8	len;
+	char	name[1];
+} ltree_level;
+
+#define LEVEL_HDRSIZE   (sizeof(uint8))
+#define LEVEL_NEXT(x)	( (ltree_level*)( ((char*)(x)) + ((ltree_level*)(x))->len + LEVEL_HDRSIZE ) )
+
+typedef struct {
+	int32	len;
+	uint16	numlevel;
+	char	data[1];
+} ltree;
+
+#define LTREE_HDRSIZE	( sizeof(int32) + sizeof(uint16) )
+#define LTREE_FIRST(x)	( (ltree_level*)( ((ltree*)(x))->data ) )
+
+
+/* lquery */
+
+typedef struct {
+	int4	val;	
+	uint8	len;
+	uint8	flag;
+	char	name[1];
+} lquery_variant;
+
+#define LVAR_HDRSIZE   (sizeof(uint8)*2 + sizeof(int4))
+#define LVAR_NEXT(x)	( (lquery_variant*)( ((char*)(x)) + ((lquery_variant*)(x))->len + LVAR_HDRSIZE ) )
+
+#define LVAR_ANYEND	0x01
+#define LVAR_INCASE	0x02
+#define LVAR_SUBLEXEM	0x04
+
+typedef struct {
+	uint16	totallen;
+	uint16  flag;
+	uint16  numvar;
+	uint16	low;
+	uint16	high;
+	char	variants[1];
+} lquery_level;
+
+#define LQL_HDRSIZE	( sizeof(uint16)*5 )
+#define LQL_NEXT(x)	( (lquery_level*)( ((char*)(x)) + ((lquery_level*)(x))->totallen ) )
+#define LQL_FIRST(x)	( (lquery_variant*)( ((lquery_level*)(x))->variants ) )
+
+#define LQL_NOT		0x10
+#ifdef LOWER_NODE
+#define FLG_CANLOOKSIGN(x) ( ( (x) & ( LQL_NOT | LVAR_ANYEND | LVAR_SUBLEXEM ) ) == 0 )
+#else
+#define FLG_CANLOOKSIGN(x) ( ( (x) & ( LQL_NOT | LVAR_ANYEND | LVAR_SUBLEXEM | LVAR_INCASE ) ) == 0 )
+#endif
+#define LQL_CANLOOKSIGN(x) FLG_CANLOOKSIGN( ((lquery_level*)(x))->flag ) 
+
+typedef struct {
+	int32   len;
+	uint16  numlevel;
+	uint16	firstgood;
+	uint16	flag;
+	char    data[1];
+} lquery; 
+
+#define LQUERY_HDRSIZE   ( sizeof(int32) + 3*sizeof(uint16) )
+#define LQUERY_FIRST(x)   ( (lquery_level*)( ((lquery*)(x))->data ) )
+
+#define LQUERY_HASNOT		0x01
+
+#ifndef max  
+#define max(a,b)                ((a) >  (b) ? (a) : (b))
+#endif
+#ifndef min
+#define min(a,b)                ((a) <= (b) ? (a) : (b))
+#endif
+#ifndef abs
+#define abs(a)                  ((a) <  (0) ? -(a) : (a))
+#endif
+#define ISALNUM(x)	( isalnum(x) || (x) == '_' )
+
+/* full text query */
+
+/*
+ * item in polish notation with back link
+ * to left operand
+ */
+typedef struct ITEM
+{
+        int2            type;
+        int2            left;
+        int4            val;
+	uint8		flag;
+        /* user-friendly value */
+        uint8          length;
+        uint16          distance;
+}       ITEM;
+
+/*
+ *Storage:
+ *      (len)(size)(array of ITEM)(array of operand in user-friendly form)
+ */
+typedef struct
+{
+        int4            len;
+        int4            size;
+        char            data[1];
+}       ltxtquery;
+
+#define HDRSIZEQT       ( 2*sizeof(int4) )
+#define COMPUTESIZE(size,lenofoperand)  ( HDRSIZEQT + size * sizeof(ITEM) + lenofoperand )
+#define GETQUERY(x)  (ITEM*)( (char*)(x)+HDRSIZEQT )
+#define GETOPERAND(x)   ( (char*)GETQUERY(x) + ((ltxtquery*)x)->size * sizeof(ITEM) )
+
+#define ISOPERATOR(x) ( (x)=='!' || (x)=='&' || (x)=='|' || (x)=='(' || (x)==')' )
+
+#define END                     0
+#define ERR                     1
+#define VAL                     2
+#define OPR                     3
+#define OPEN                    4
+#define CLOSE                   5
+#define VALTRUE                 6               /* for stop words */
+#define VALFALSE                7
+
+
+/* use in array iterator */
+Datum   ltree_isparent(PG_FUNCTION_ARGS);
+Datum   ltree_risparent(PG_FUNCTION_ARGS);
+Datum ltq_regex(PG_FUNCTION_ARGS);
+Datum ltq_rregex(PG_FUNCTION_ARGS);
+Datum      ltxtq_exec(PG_FUNCTION_ARGS);
+Datum      ltxtq_rexec(PG_FUNCTION_ARGS);
+Datum   _ltq_regex(PG_FUNCTION_ARGS);
+Datum   _ltq_rregex(PG_FUNCTION_ARGS);
+Datum   _ltxtq_exec(PG_FUNCTION_ARGS);
+Datum   _ltxtq_rexec(PG_FUNCTION_ARGS);
+Datum   _ltree_isparent(PG_FUNCTION_ARGS);
+Datum   _ltree_risparent(PG_FUNCTION_ARGS);
+
+/* Concatenation functions */
+Datum   ltree_addltree(PG_FUNCTION_ARGS);
+Datum   ltree_addtext(PG_FUNCTION_ARGS);
+Datum   ltree_textadd(PG_FUNCTION_ARGS);
+
+/* Util function */
+Datum ltree_in(PG_FUNCTION_ARGS);
+
+bool execute(ITEM * curitem, void *checkval,
+                bool calcnot, bool (*chkcond) (void *checkval, ITEM * val));
+
+int ltree_compare(const ltree *a, const ltree *b);
+bool inner_isparent(const ltree *c, const ltree *p);
+bool compare_subnode( ltree_level *t, char *q, int len, 
+	int (*cmpptr)(const char *,const char *,size_t), bool anyend );
+
+#define PG_GETARG_LTREE(x)  ((ltree*)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(x))))
+#define PG_GETARG_LQUERY(x) ((lquery*)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(x))))
+#define PG_GETARG_LTXTQUERY(x) ((ltxtquery*)DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(x))))
+
+/* GiST support for ltree */
+
+#define BITBYTE 8
+#define SIGLENINT  8
+#define SIGLEN  ( sizeof(int4)*SIGLENINT )
+#define SIGLENBIT (SIGLEN*BITBYTE)
+typedef unsigned char BITVEC[SIGLEN];
+typedef unsigned char *BITVECP;
+
+#define LOOPBYTE(a) \
+	for(i=0;i<SIGLEN;i++) {\
+		a;\
+	}
+#define LOOPBIT(a) \
+	for(i=0;i<SIGLENBIT;i++) {\
+		a;\
+	}
+
+#define GETBYTE(x,i) ( *( (BITVECP)(x) + (int)( (i) / BITBYTE ) ) )
+#define GETBITBYTE(x,i) ( ((unsigned char)(x)) >> i & 0x01 )
+#define CLRBIT(x,i)   GETBYTE(x,i) &= ~( 0x01 << ( (i) % BITBYTE ) )
+#define SETBIT(x,i)   GETBYTE(x,i) |=  ( 0x01 << ( (i) % BITBYTE ) )
+#define GETBIT(x,i) ( (GETBYTE(x,i) >> ( (i) % BITBYTE )) & 0x01 )
+
+#define HASHVAL(val) (((unsigned int)(val)) % SIGLENBIT)
+#define HASH(sign, val) SETBIT((sign), HASHVAL(val))
+
+/*
+ * type of index key for ltree. Tree are combined B-Tree and R-Tree
+ * Storage:
+ * 	Leaf pages 
+ *		(len)(flag)(ltree)
+ *	Non-Leaf
+ *		         (len)(flag)(sign)(left_ltree)(right_ltree)
+ *		ALLTRUE: (len)(flag)(left_ltree)(right_ltree)
+ *	
+ */
+
+typedef struct {
+	int4 len;
+	uint32	flag;
+	char	data[1];
+} ltree_gist;
+
+#define	LTG_ONENODE	0x01
+#define	LTG_ALLTRUE	0x02
+#define	LTG_NORIGHT	0x04
+
+#define LTG_HDRSIZE	( sizeof(int4) + sizeof(uint32) )
+#define LTG_SIGN(x)	( (BITVECP)( ((ltree_gist*)(x))->data ) ) 
+#define LTG_NODE(x)	( (ltree*)( ((ltree_gist*)(x))->data ) )
+#define LTG_ISONENODE(x) ( ((ltree_gist*)(x))->flag & LTG_ONENODE ) 
+#define LTG_ISALLTRUE(x) ( ((ltree_gist*)(x))->flag & LTG_ALLTRUE ) 
+#define LTG_ISNORIGHT(x) ( ((ltree_gist*)(x))->flag & LTG_NORIGHT ) 
+#define LTG_LNODE(x)	( (ltree*)( ( (char*)( ((ltree_gist*)(x))->data ) ) + ( LTG_ISALLTRUE(x) ? 0 : SIGLEN ) ) )
+#define LTG_RENODE(x)	( (ltree*)( ((char*)LTG_LNODE(x)) + LTG_LNODE(x)->len ) )
+#define LTG_RNODE(x)	( LTG_ISNORIGHT(x) ? LTG_LNODE(x) : LTG_RENODE(x) )
+
+#define LTG_GETLNODE(x)	( LTG_ISONENODE(x) ? LTG_NODE(x) : LTG_LNODE(x) ) 
+#define LTG_GETRNODE(x)	( LTG_ISONENODE(x) ? LTG_NODE(x) : LTG_RNODE(x) ) 
+
+
+/* GiST support for ltree[] */
+
+#define ASIGLENINT 	(2*SIGLENINT)
+#define ASIGLEN		(sizeof(int4)*ASIGLENINT)
+#define	ASIGLENBIT (ASIGLEN*BITBYTE)
+typedef unsigned char ABITVEC[ASIGLEN];
+
+#define ALOOPBYTE(a) \
+	for(i=0;i<ASIGLEN;i++) {\
+		a;\
+	}
+#define ALOOPBIT(a) \
+	for(i=0;i<ASIGLENBIT;i++) {\
+		a;\
+	}
+
+#define AHASHVAL(val) (((unsigned int)(val)) % ASIGLENBIT)
+#define AHASH(sign, val) SETBIT((sign), AHASHVAL(val))
+
+/* type of key is the same to ltree_gist */
+
+#endif
+
--- a/contrib/ltree/ltree.sql.in
+++ b/contrib/ltree/ltree.sql.in
@ -0,0 +1,849 @@
+BEGIN;
+
+CREATE FUNCTION ltree_in(opaque)
+RETURNS opaque
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict);
+
+CREATE FUNCTION ltree_out(opaque)
+RETURNS opaque
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict);
+
+CREATE TYPE ltree (
+internallength = -1,
+input = ltree_in,
+output = ltree_out,
+storage = extended
+);
+
+
+--Compare function for ltree
+CREATE FUNCTION ltree_cmp(ltree,ltree)
+RETURNS int4
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_lt(ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_le(ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_eq(ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_ge(ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_gt(ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_ne(ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+
+CREATE OPERATOR < (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_lt,
+        COMMUTATOR = '>', NEGATOR = '>=',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR <= (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_le,
+        COMMUTATOR = '>=', NEGATOR = '>',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR >= (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_ge,
+        COMMUTATOR = '<=', NEGATOR = '<',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR > (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_gt,
+        COMMUTATOR = '<', NEGATOR = '<=',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR = (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_eq,
+        COMMUTATOR = '=', NEGATOR = '<>',
+        RESTRICT = eqsel, JOIN = eqjoinsel,
+        SORT1 = '<', SORT2 = '<'
+);
+
+CREATE OPERATOR <> (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_ne,
+        COMMUTATOR = '<>', NEGATOR = '=',
+        RESTRICT = neqsel, JOIN = neqjoinsel
+);
+
+--util functions
+
+CREATE FUNCTION subltree(ltree,int4,int4)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION subpath(ltree,int4,int4)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION subpath(ltree,int4)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION nlevel(ltree)
+RETURNS int4
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_isparent(ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_risparent(ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_addltree(ltree,ltree)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_addtext(ltree,text)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltree_textadd(text,ltree)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE OPERATOR @> (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_isparent,
+        COMMUTATOR = '<@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^@> (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_isparent,
+        COMMUTATOR = '^<@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR <@ (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_risparent,
+        COMMUTATOR = '@>',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^<@ (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_risparent,
+        COMMUTATOR = '^@>',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR || (
+        LEFTARG = ltree, RIGHTARG = ltree, PROCEDURE = ltree_addltree
+);
+
+CREATE OPERATOR || (
+        LEFTARG = ltree, RIGHTARG = text, PROCEDURE = ltree_addtext
+);
+
+CREATE OPERATOR || (
+        LEFTARG = text, RIGHTARG = ltree, PROCEDURE = ltree_textadd
+);
+
+
+-- B-tree support
+INSERT INTO pg_opclass (opcamid, opcname, opcnamespace, opcowner, opcintype, opcdefault, opckeytype)
+    VALUES (
+        (SELECT oid FROM pg_am WHERE amname = 'btree'),
+        'ltree_ops',
+	(SELECT oid FROM pg_namespace WHERE nspname = 'pg_catalog'),
+	1,      -- UID of superuser is hardwired to 1 as of PG 7.3
+        (SELECT oid FROM pg_type WHERE typname = 'ltree'),
+        true,
+        0);
+
+SELECT o.oid AS opoid, o.oprname
+    INTO TEMP TABLE ltree_ops_tmp
+    FROM pg_operator o, pg_type t
+    WHERE o.oprleft = t.oid and o.oprright = t.oid
+      and t.typname = 'ltree';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+    SELECT opcl.oid, 1, false, c.opoid
+        FROM pg_opclass opcl, ltree_ops_tmp c
+        WHERE
+            opcamid = (SELECT oid FROM pg_am WHERE amname = 'btree') AND
+            opcname = 'ltree_ops' AND
+            c.oprname = '<';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+    SELECT opcl.oid, 2, false, c.opoid
+        FROM pg_opclass opcl, ltree_ops_tmp c
+        WHERE
+            opcamid = (SELECT oid FROM pg_am WHERE amname = 'btree') AND
+            opcname = 'ltree_ops' AND
+            c.oprname = '<=';
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+    SELECT opcl.oid, 3, false, c.opoid
+        FROM pg_opclass opcl, ltree_ops_tmp c
+        WHERE
+            opcamid = (SELECT oid FROM pg_am WHERE amname = 'btree') AND
+            opcname = 'ltree_ops' AND
+            c.oprname = '=';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+    SELECT opcl.oid, 4, false, c.opoid
+        FROM pg_opclass opcl, ltree_ops_tmp c
+        WHERE
+            opcamid = (SELECT oid FROM pg_am WHERE amname = 'btree') AND
+            opcname = 'ltree_ops' AND
+            c.oprname = '>=';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+    SELECT opcl.oid, 5, false, c.opoid
+        FROM pg_opclass opcl, ltree_ops_tmp c
+        WHERE
+            opcamid = (SELECT oid FROM pg_am WHERE amname = 'btree') AND
+            opcname = 'ltree_ops' AND
+            c.oprname = '>';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+    SELECT opcl.oid, 1, p.oid
+        FROM pg_opclass opcl, pg_proc p
+        WHERE
+            opcamid = (SELECT oid FROM pg_am WHERE amname = 'btree') AND
+            opcname = 'ltree_ops' AND
+            p.proname = 'ltree_cmp';
+
+drop table ltree_ops_tmp;
+
+--lquery type
+CREATE FUNCTION lquery_in(opaque)
+RETURNS opaque
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict);
+
+CREATE FUNCTION lquery_out(opaque)
+RETURNS opaque
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict);
+
+CREATE TYPE lquery (
+internallength = -1,
+input = lquery_in,
+output = lquery_out,
+storage = extended
+);
+
+CREATE FUNCTION ltq_regex(ltree,lquery)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION ltq_rregex(lquery,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE OPERATOR ~ (
+        LEFTARG = ltree, RIGHTARG = lquery, PROCEDURE = ltq_regex,
+	COMMUTATOR = '~',
+	RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ~ (
+        LEFTARG = lquery, RIGHTARG = ltree, PROCEDURE = ltq_rregex,
+	COMMUTATOR = '~',
+	RESTRICT = contsel, JOIN = contjoinsel
+);
+
+--not-indexed
+CREATE OPERATOR ^~ (
+        LEFTARG = ltree, RIGHTARG = lquery, PROCEDURE = ltq_regex,
+	COMMUTATOR = '^~',
+	RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^~ (
+        LEFTARG = lquery, RIGHTARG = ltree, PROCEDURE = ltq_rregex,
+	COMMUTATOR = '^~',
+	RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE FUNCTION ltxtq_in(opaque)
+RETURNS opaque
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict);
+
+CREATE FUNCTION ltxtq_out(opaque)
+RETURNS opaque
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict);
+
+CREATE TYPE ltxtquery (
+internallength = -1,
+input = ltxtq_in,
+output = ltxtq_out,
+storage = extended
+);
+
+-- operations with ltxtquery
+
+CREATE FUNCTION ltxtq_exec(ltree, ltxtquery)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict, iscachable);
+
+CREATE FUNCTION ltxtq_rexec(ltxtquery, ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict, iscachable);
+
+CREATE OPERATOR @ (
+        LEFTARG = ltree, RIGHTARG = ltxtquery, PROCEDURE = ltxtq_exec,
+	COMMUTATOR = '@',
+	RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR @ (
+        LEFTARG = ltxtquery, RIGHTARG = ltree, PROCEDURE = ltxtq_rexec,
+	COMMUTATOR = '@',
+	RESTRICT = contsel, JOIN = contjoinsel
+);
+
+--not-indexed
+CREATE OPERATOR ^@ (
+        LEFTARG = ltree, RIGHTARG = ltxtquery, PROCEDURE = ltxtq_exec,
+	COMMUTATOR = '^@',
+	RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^@ (
+        LEFTARG = ltxtquery, RIGHTARG = ltree, PROCEDURE = ltxtq_rexec,
+	COMMUTATOR = '^@',
+	RESTRICT = contsel, JOIN = contjoinsel
+);
+
+--GiST support for ltree
+CREATE FUNCTION ltree_gist_in(opaque)
+RETURNS opaque
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict);
+   
+CREATE FUNCTION ltree_gist_out(opaque)
+RETURNS opaque
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict);
+   
+CREATE TYPE ltree_gist (
+	internallength = -1,
+	input = ltree_gist_in,
+	output = ltree_gist_out,
+	storage = plain
+);    
+
+
+create function ltree_consistent(opaque,opaque,int2) returns bool as 'MODULE_PATHNAME' language 'C';
+create function ltree_compress(opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+create function ltree_decompress(opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+create function ltree_penalty(opaque,opaque,opaque) returns opaque as 'MODULE_PATHNAME' language 'C' with(isstrict);
+create function ltree_picksplit(opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+create function ltree_union(bytea, opaque) returns int4 as 'MODULE_PATHNAME' language 'C';
+create function ltree_same(opaque, opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+
+INSERT INTO pg_opclass (opcamid, opcname, opcnamespace, opcowner, opcintype, opckeytype, opcdefault)
+   SELECT pg_am.oid, 'gist_ltree_ops', 
+	(SELECT oid FROM pg_namespace WHERE nspname = 'pg_catalog'),
+	1,      -- UID of superuser is hardwired to 1 as of PG 7.3
+	pg_type.oid, pg_key.oid, true
+   FROM pg_type, pg_am, pg_type pg_key
+   WHERE pg_type.typname = 'ltree' and
+   pg_am.amname='gist' and
+   pg_key.typname = 'ltree_gist';
+
+SELECT o.oid AS opoid, o.oprname
+INTO TABLE ltree_ops_tmp
+FROM pg_operator o, pg_type t
+WHERE o.oprleft = t.oid and o.oprright = t.oid
+   and t.typname = 'ltree';
+
+INSERT INTO pg_amop (amopclaid, amopopr, amopstrategy, amopreqcheck)
+   SELECT opcl.oid, c.opoid, 1, 'f'
+   FROM pg_opclass opcl, ltree_ops_tmp c
+   WHERE opcname = 'gist_ltree_ops'
+      and c.oprname = '<';
+
+INSERT INTO pg_amop (amopclaid, amopopr, amopstrategy, amopreqcheck)
+   SELECT opcl.oid, c.opoid, 2, 'f'
+   FROM pg_opclass opcl, ltree_ops_tmp c
+   WHERE opcname = 'gist_ltree_ops'
+      and c.oprname = '<=';
+
+INSERT INTO pg_amop (amopclaid, amopopr, amopstrategy, amopreqcheck)
+   SELECT opcl.oid, c.opoid, 3, 'f'
+   FROM pg_opclass opcl, ltree_ops_tmp c
+   WHERE opcname = 'gist_ltree_ops'
+      and c.oprname = '=';
+
+INSERT INTO pg_amop (amopclaid, amopopr, amopstrategy, amopreqcheck)
+   SELECT opcl.oid, c.opoid, 4, 'f'
+   FROM pg_opclass opcl, ltree_ops_tmp c
+   WHERE opcname = 'gist_ltree_ops'
+      and c.oprname = '>=';
+
+INSERT INTO pg_amop (amopclaid, amopopr, amopstrategy, amopreqcheck)
+   SELECT opcl.oid, c.opoid, 5, 'f'
+   FROM pg_opclass opcl, ltree_ops_tmp c
+   WHERE opcname = 'gist_ltree_ops'
+      and c.oprname = '>';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 10, false, c.opoid
+   FROM pg_opclass opcl, ltree_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and c.oprname = '@>';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 11, false, c.opoid
+   FROM pg_opclass opcl, ltree_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and c.oprname = '<@';
+
+DROP TABLE ltree_ops_tmp;
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 12, false, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and t.typname = 'ltree' and tq.typname = 'lquery'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '~';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 13, false, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and t.typname = 'lquery' and tq.typname = 'ltree'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '~';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 14, false, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and t.typname = 'ltree' and tq.typname = 'ltxtquery'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '@';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 15, false, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and t.typname = 'ltxtquery' and tq.typname = 'ltree'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '@';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 1, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and proname = 'ltree_consistent';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 2, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and proname = 'ltree_union';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 3, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and proname = 'ltree_compress';
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 4, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and proname = 'ltree_decompress';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 5, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and proname = 'ltree_penalty';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 6, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and proname = 'ltree_picksplit';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 7, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_ltree_ops'
+      and proname = 'ltree_same';
+
+-- arrays of ltree
+
+CREATE FUNCTION _ltree_isparent(_ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION _ltree_r_isparent(ltree,_ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION _ltree_risparent(_ltree,ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION _ltree_r_risparent(ltree,_ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION _ltq_regex(_ltree,lquery)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION _ltq_rregex(lquery,_ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE FUNCTION _ltxtq_exec(_ltree, ltxtquery)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict, iscachable);
+
+CREATE FUNCTION _ltxtq_rexec(ltxtquery, _ltree)
+RETURNS bool
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict, iscachable);
+
+CREATE OPERATOR @> (
+        LEFTARG = _ltree, RIGHTARG = ltree, PROCEDURE = _ltree_isparent,
+        COMMUTATOR = '<@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR <@ (
+        LEFTARG = ltree, RIGHTARG = _ltree, PROCEDURE = _ltree_r_isparent,
+        COMMUTATOR = '@>',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR <@ (
+        LEFTARG = _ltree, RIGHTARG = ltree, PROCEDURE = _ltree_risparent,
+        COMMUTATOR = '@>',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR @> (
+        LEFTARG = ltree, RIGHTARG = _ltree, PROCEDURE = _ltree_r_risparent,
+        COMMUTATOR = '<@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ~ (
+        LEFTARG = _ltree, RIGHTARG = lquery, PROCEDURE = _ltq_regex,
+        COMMUTATOR = '~',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ~ (
+        LEFTARG = lquery, RIGHTARG = _ltree, PROCEDURE = _ltq_rregex,
+        COMMUTATOR = '~',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR @ (
+        LEFTARG = _ltree, RIGHTARG = ltxtquery, PROCEDURE = _ltxtq_exec,
+        COMMUTATOR = '@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR @ (
+        LEFTARG = ltxtquery, RIGHTARG = _ltree, PROCEDURE = _ltxtq_rexec,
+        COMMUTATOR = '@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+
+--not indexed
+CREATE OPERATOR ^@> (
+        LEFTARG = _ltree, RIGHTARG = ltree, PROCEDURE = _ltree_isparent,
+        COMMUTATOR = '^<@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^<@ (
+        LEFTARG = ltree, RIGHTARG = _ltree, PROCEDURE = _ltree_r_isparent,
+        COMMUTATOR = '^@>',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^<@ (
+        LEFTARG = _ltree, RIGHTARG = ltree, PROCEDURE = _ltree_risparent,
+        COMMUTATOR = '^@>',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^@> (
+        LEFTARG = ltree, RIGHTARG = _ltree, PROCEDURE = _ltree_r_risparent,
+        COMMUTATOR = '^<@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^~ (
+        LEFTARG = _ltree, RIGHTARG = lquery, PROCEDURE = _ltq_regex,
+        COMMUTATOR = '^~',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^~ (
+        LEFTARG = lquery, RIGHTARG = _ltree, PROCEDURE = _ltq_rregex,
+        COMMUTATOR = '^~',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^@ (
+        LEFTARG = _ltree, RIGHTARG = ltxtquery, PROCEDURE = _ltxtq_exec,
+        COMMUTATOR = '^@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+CREATE OPERATOR ^@ (
+        LEFTARG = ltxtquery, RIGHTARG = _ltree, PROCEDURE = _ltxtq_rexec,
+        COMMUTATOR = '^@',
+        RESTRICT = contsel, JOIN = contjoinsel
+);
+
+--extractors
+CREATE FUNCTION _ltree_extract_isparent(_ltree,ltree)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE OPERATOR ?@> (
+        LEFTARG = _ltree, RIGHTARG = ltree, PROCEDURE = _ltree_extract_isparent
+);
+
+CREATE FUNCTION _ltree_extract_risparent(_ltree,ltree)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE OPERATOR ?<@ (
+        LEFTARG = _ltree, RIGHTARG = ltree, PROCEDURE = _ltree_extract_risparent
+);
+
+CREATE FUNCTION _ltq_extract_regex(_ltree,lquery)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE OPERATOR ?~ (
+        LEFTARG = _ltree, RIGHTARG = lquery, PROCEDURE = _ltq_extract_regex
+);
+
+CREATE FUNCTION _ltxtq_extract_exec(_ltree,ltxtquery)
+RETURNS ltree
+AS 'MODULE_PATHNAME'
+LANGUAGE 'c' with (isstrict,iscachable);
+
+CREATE OPERATOR ?@ (
+        LEFTARG = _ltree, RIGHTARG = ltxtquery, PROCEDURE = _ltxtq_extract_exec
+);
+
+--GiST support for ltree[]
+create function _ltree_consistent(opaque,opaque,int2) returns bool as 'MODULE_PATHNAME' language 'C';
+create function _ltree_compress(opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+create function _ltree_penalty(opaque,opaque,opaque) returns opaque as 'MODULE_PATHNAME' language 'C' with(isstrict);
+create function _ltree_picksplit(opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+create function _ltree_union(bytea, opaque) returns int4 as 'MODULE_PATHNAME' language 'C';
+create function _ltree_same(opaque, opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+
+INSERT INTO pg_opclass (opcamid, opcname, opcnamespace, opcowner, opcintype, opckeytype, opcdefault)
+   SELECT pg_am.oid, 'gist__ltree_ops', 
+	(SELECT oid FROM pg_namespace WHERE nspname = 'pg_catalog'),
+	1,      -- UID of superuser is hardwired to 1 as of PG 7.3
+	pg_type.oid, pg_key.oid, true
+   FROM pg_type, pg_am, pg_type pg_key
+   WHERE pg_type.typname = '_ltree' and
+   pg_am.amname='gist' and
+   pg_key.typname = 'ltree_gist';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 12, true, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and t.typname = '_ltree' and tq.typname = 'lquery'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '~';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 13, true, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and t.typname = 'lquery' and tq.typname = '_ltree'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '~';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 14, true, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and t.typname = '_ltree' and tq.typname = 'ltxtquery'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '@';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 15, true, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and t.typname = 'ltxtquery' and tq.typname = '_ltree'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '@';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 10, true, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and t.typname = '_ltree' and tq.typname = 'ltree'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '<@';
+
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 11, true, o.oid
+   FROM pg_opclass opcl, pg_operator o, pg_type t, pg_type tq
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and t.typname = 'ltree' and tq.typname = '_ltree'
+      and o.oprleft = t.oid and o.oprright = tq.oid 
+      and o.oprname = '@>';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 1, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and proname = '_ltree_consistent';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 2, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and proname = '_ltree_union';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 3, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and proname = '_ltree_compress';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 4, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and proname = 'ltree_decompress';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 5, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and proname = '_ltree_penalty';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 6, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and proname = '_ltree_picksplit';
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 7, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist__ltree_ops'
+      and proname = '_ltree_same';
+
+END;
--- a/contrib/ltree/ltree_gist.c
+++ b/contrib/ltree/ltree_gist.c
@ -0,0 +1,600 @@
+/*
+ * GiST support for ltree 
+ * Teodor Sigaev <teodor@stack.net>
+ */
+
+#include "ltree.h"
+#include "access/gist.h"
+#include "access/rtree.h"
+#include "access/nbtree.h"
+
+#include "crc32.h"
+
+PG_FUNCTION_INFO_V1( ltree_gist_in );
+Datum   ltree_gist_in(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( ltree_gist_out );
+Datum   ltree_gist_out(PG_FUNCTION_ARGS);
+
+Datum
+ltree_gist_in(PG_FUNCTION_ARGS) {
+	elog(ERROR,"Unimplemented");
+	PG_RETURN_DATUM(0);
+}
+
+Datum
+ltree_gist_out(PG_FUNCTION_ARGS) {
+	elog(ERROR,"Unimplemented");
+	PG_RETURN_DATUM(0);
+}
+
+PG_FUNCTION_INFO_V1( ltree_compress );
+Datum   ltree_compress(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( ltree_decompress );
+Datum   ltree_decompress(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( ltree_same );
+Datum   ltree_same(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( ltree_union );
+Datum   ltree_union(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( ltree_penalty );
+Datum   ltree_penalty(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( ltree_picksplit );
+Datum   ltree_picksplit(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1( ltree_consistent );
+Datum   ltree_consistent(PG_FUNCTION_ARGS);
+
+#define ISEQ(a,b)	( (a)->numlevel == (b)->numlevel && ltree_compare(a,b)==0 )
+#define GETENTRY(vec,pos) ((ltree_gist *) DatumGetPointer(((GISTENTRY *) VARDATA(vec))[(pos)].key))
+
+Datum   
+ltree_compress(PG_FUNCTION_ARGS) {
+	GISTENTRY *entry = (GISTENTRY *)PG_GETARG_POINTER(0);
+	GISTENTRY  *retval = entry;
+
+	if ( entry->leafkey ) { /* ltree */
+		ltree_gist	*key;
+		ltree	*val = (ltree*)DatumGetPointer(PG_DETOAST_DATUM(entry->key));
+		int4 len = LTG_HDRSIZE + val->len;
+
+		key = (ltree_gist*)palloc( len );
+		key->len = len;
+		key->flag = LTG_ONENODE;
+		memcpy( (void*)LTG_NODE(key), (void*)val, val->len);
+
+		if ( PointerGetDatum(val) != entry->key )
+			pfree(val);
+
+		retval = (GISTENTRY*)palloc( sizeof(GISTENTRY) );
+		gistentryinit(*retval, PointerGetDatum(key),
+			entry->rel, entry->page,
+			entry->offset, key->len, FALSE);
+	}
+	PG_RETURN_POINTER(retval);
+}
+
+Datum   
+ltree_decompress(PG_FUNCTION_ARGS) {
+	GISTENTRY *entry = (GISTENTRY *)PG_GETARG_POINTER(0);
+	ltree_gist *key = (ltree_gist*)DatumGetPointer( PG_DETOAST_DATUM(entry->key) );
+
+	if ( PointerGetDatum(key) != entry->key ) {
+		GISTENTRY *retval = (GISTENTRY*)palloc(sizeof(GISTENTRY));
+		gistentryinit(*retval, PointerGetDatum(key),
+			entry->rel, entry->page,
+			entry->offset, key->len, FALSE);
+		PG_RETURN_POINTER(retval);
+	}
+	 PG_RETURN_POINTER(entry);
+}
+
+Datum   
+ltree_same(PG_FUNCTION_ARGS) {
+	ltree_gist*	a=(ltree_gist*)PG_GETARG_POINTER(0);
+	ltree_gist*	b=(ltree_gist*)PG_GETARG_POINTER(1);
+	bool *result = (bool *)PG_GETARG_POINTER(2);
+
+	*result = false;
+	if ( LTG_ISONENODE(a) != LTG_ISONENODE(b) )
+		PG_RETURN_POINTER(result); 
+		
+	if ( LTG_ISONENODE(a) ) {
+		*result = ( ISEQ(LTG_NODE(a), LTG_NODE(b)) ) ? true : false;
+	} else {
+		int4 i;
+		BITVECP sa=LTG_SIGN(a), sb=LTG_SIGN(b);
+ 
+		if ( LTG_ISALLTRUE(a) != LTG_ISALLTRUE(b) ) 
+			 PG_RETURN_POINTER(result);
+
+		if ( !ISEQ(LTG_LNODE(a), LTG_LNODE(b)) ) 
+			PG_RETURN_POINTER(result); 
+		if ( !ISEQ(LTG_RNODE(a), LTG_RNODE(b)) ) 
+			PG_RETURN_POINTER(result);
+
+		*result = true;
+		if ( !LTG_ISALLTRUE(a) )
+			LOOPBYTE(
+				if ( sa[i] != sb[i] ) {
+					*result = false;
+					break;
+				}
+			);
+	}
+ 
+	PG_RETURN_POINTER(result); 
+}
+
+static void
+hashing(BITVECP sign, ltree *t) {
+	int tlen = t->numlevel;
+	ltree_level *cur = LTREE_FIRST(t);
+	int  hash;
+
+	while(tlen > 0) {
+		hash = crc32_sz( cur->name, cur->len );
+		HASH( sign, hash );
+		cur = LEVEL_NEXT(cur);
+		tlen--;
+	}
+}
+
+Datum   
+ltree_union(PG_FUNCTION_ARGS) {
+	bytea *entryvec = (bytea *) PG_GETARG_POINTER(0);
+	int *size = (int *) PG_GETARG_POINTER(1);
+	BITVEC base;
+	int4 len = (VARSIZE(entryvec) - VARHDRSZ) / sizeof(GISTENTRY);
+	int4 i,j;
+	ltree_gist	*result,*cur;
+	ltree	*left=NULL, *right=NULL, *curtree;
+	bool	isalltrue = false;
+	bool    isleqr;
+
+	MemSet( (void*)base, 0, sizeof(BITVEC) );
+	for(j=0;j<len;j++) {
+		cur = GETENTRY(entryvec, j);
+		if ( LTG_ISONENODE(cur) ) {
+			curtree = LTG_NODE(cur);
+			hashing(base,curtree);
+			if ( !left || ltree_compare( left, curtree ) > 0 )
+				left =  curtree;
+			if ( !right || ltree_compare( right, curtree ) < 0 ) 
+				right = curtree;
+		} else {
+			if ( isalltrue || LTG_ISALLTRUE(cur) ) 
+				isalltrue = true;
+			else { 
+				BITVECP sc=LTG_SIGN(cur);
+				LOOPBYTE(
+					((unsigned char*)base)[i] |= sc[i];
+				);
+			}
+
+			curtree = LTG_LNODE(cur);
+			if ( !left || ltree_compare( left, curtree ) > 0 )
+				left =  curtree;
+			curtree = LTG_RNODE(cur);
+			if ( !right || ltree_compare( right, curtree ) < 0 ) 
+				right = curtree;
+		} 
+	}
+	
+	if ( isalltrue == false ) {
+		isalltrue = true;
+		LOOPBYTE(
+			if ( ((unsigned char*)base)[i] != 0xff ) {
+				isalltrue = false;
+				break;
+			}
+		); 
+	}
+
+	isleqr = ( left==right || ISEQ(left,right) ) ? true : false; 
+	*size = LTG_HDRSIZE + ( (isalltrue) ? 0 : SIGLEN ) + left->len + ( (isleqr) ? 0 : right->len );
+
+	result = (ltree_gist*)palloc( *size );
+	result->len = *size;
+	result->flag = 0;
+
+	if ( isalltrue )
+		result->flag |= LTG_ALLTRUE;
+	else
+		memcpy( (void*)LTG_SIGN(result), base, SIGLEN );
+
+	memcpy( (void*)LTG_LNODE(result), (void*)left, left->len );
+	if ( isleqr )
+		result->flag |= LTG_NORIGHT;
+	else
+		memcpy( (void*)LTG_RNODE(result), (void*)right, right->len );
+
+	PG_RETURN_POINTER(result);	
+}
+
+Datum   
+ltree_penalty(PG_FUNCTION_ARGS) {
+	ltree_gist *origval = (ltree_gist*)DatumGetPointer( ( (GISTENTRY *)PG_GETARG_POINTER(0) )->key );
+	ltree_gist *newval  = (ltree_gist*)DatumGetPointer( ( (GISTENTRY *)PG_GETARG_POINTER(1) )->key );
+	float  *penalty = (float *)    PG_GETARG_POINTER(2);
+	int4 cmpr,cmpl;
+
+	cmpl = ltree_compare( LTG_GETLNODE(origval), LTG_GETLNODE(newval) );
+	cmpr = ltree_compare( LTG_GETRNODE(newval),  LTG_GETRNODE(origval));
+
+	*penalty = max( cmpl, 0 ) + max( cmpr, 0 );
+
+	PG_RETURN_POINTER(penalty);
+}
+
+/* used for sorting */
+typedef struct rix {
+        int         index;
+        ltree       *r;
+}       RIX;
+
+static int
+treekey_cmp(const void *a, const void *b) {
+	return ltree_compare(
+		((RIX *) a)->r,
+		((RIX *) b)->r
+	);
+}
+
+
+Datum   
+ltree_picksplit(PG_FUNCTION_ARGS) {
+	bytea *entryvec = (bytea*) PG_GETARG_POINTER(0);
+	GIST_SPLITVEC *v = (GIST_SPLITVEC*) PG_GETARG_POINTER(1);
+	OffsetNumber j;
+	int4 i;
+	RIX *array;
+	OffsetNumber maxoff;
+	int     nbytes;
+	int    size;
+	ltree	*lu_l,*lu_r, *ru_l, *ru_r;
+	ltree_gist	 *lu, *ru;
+	BITVEC	ls,rs;
+	bool	lisat=false, risat=false, isleqr;
+	
+	memset( (void*)ls,0,sizeof(BITVEC) );	
+	memset( (void*)rs,0,sizeof(BITVEC) );	
+	maxoff = ((VARSIZE(entryvec) - VARHDRSZ) / sizeof(GISTENTRY)) - 1;
+	nbytes = (maxoff + 2) * sizeof(OffsetNumber);
+	v->spl_left = (OffsetNumber *) palloc(nbytes);
+	v->spl_right = (OffsetNumber *) palloc(nbytes);
+	v->spl_nleft = 0;
+	v->spl_nright = 0;
+	array = (RIX *) palloc(sizeof(RIX) * (maxoff + 1));
+	
+	/* copy the data into RIXes, and sort the RIXes */
+	for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j)) {
+		array[j].index = j;
+		lu = GETENTRY( entryvec, j ); /* use as tmp val */
+		array[j].r = LTG_GETLNODE(lu);
+	}
+
+	qsort((void *) &array[FirstOffsetNumber], maxoff - FirstOffsetNumber + 1,
+		sizeof(RIX), treekey_cmp);
+
+	lu_l = lu_r = ru_l = ru_r = NULL;
+	for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j)) {
+		lu = GETENTRY( entryvec, array[j].index ); /* use as tmp val */
+		if (j <= (maxoff - FirstOffsetNumber + 1) / 2) {
+			v->spl_left[v->spl_nleft] = array[j].index;
+			v->spl_nleft++;
+			if ( lu_r==NULL || ltree_compare( LTG_GETRNODE(lu), lu_r ) > 0 )
+				lu_r = LTG_GETRNODE(lu);
+			if ( LTG_ISONENODE(lu) )
+				hashing(ls,LTG_NODE(lu));
+			else { 
+				if ( lisat || LTG_ISALLTRUE(lu) ) 
+					lisat = true;
+				else { 
+					BITVECP sc=LTG_SIGN(lu);
+					LOOPBYTE(
+						((unsigned char*)ls)[i] |= sc[i];
+					);
+				}
+			}
+		} else {
+			v->spl_right[v->spl_nright] = array[j].index;
+			v->spl_nright++;
+			if ( ru_r==NULL || ltree_compare( LTG_GETRNODE(lu), ru_r ) > 0 )
+				ru_r = LTG_GETRNODE(lu);
+			if ( LTG_ISONENODE(lu) )
+				hashing(rs,LTG_NODE(lu));
+			else { 
+				if ( risat || LTG_ISALLTRUE(lu) ) 
+					risat = true;
+				else { 
+					BITVECP sc=LTG_SIGN(lu);
+					LOOPBYTE(
+						((unsigned char*)rs)[i] |= sc[i];
+					);
+				}
+			}
+		}
+	}
+	
+	if ( lisat == false ) {
+		lisat = true;
+		LOOPBYTE(
+			if ( ((unsigned char*)ls)[i] != 0xff ) {
+				lisat = false;
+				break;
+			}
+		); 
+	}
+
+	if ( risat == false ) {
+		risat = true;
+		LOOPBYTE(
+			if ( ((unsigned char*)rs)[i] != 0xff ) {
+				risat = false;
+				break;
+			}
+		); 
+	}
+
+	lu_l = LTG_GETLNODE( GETENTRY( entryvec, array[FirstOffsetNumber].index ) );
+	isleqr = ( lu_l==lu_r || ISEQ(lu_l,lu_r) ) ? true : false; 
+	size = LTG_HDRSIZE + ( (lisat) ? 0 : SIGLEN ) + lu_l->len + ( (isleqr) ? 0 : lu_r->len );
+	lu = (ltree_gist*)palloc( size );
+	lu->len = size;
+	lu->flag = 0;
+	if ( lisat )
+		lu->flag |= LTG_ALLTRUE;
+	else
+		memcpy( (void*)LTG_SIGN(lu), ls, SIGLEN );
+	memcpy( (void*)LTG_LNODE(lu), (void*)lu_l, lu_l->len );
+	if ( isleqr )
+		lu->flag |= LTG_NORIGHT;
+	else
+		memcpy( (void*)LTG_RNODE(lu), (void*)lu_r, lu_r->len );
+
+
+	ru_l = LTG_GETLNODE( GETENTRY( entryvec, array[ 1 + ((maxoff - FirstOffsetNumber + 1) / 2) ].index ) );
+	isleqr = ( ru_l==ru_r || ISEQ(ru_l,ru_r) ) ? true : false;
+	size = LTG_HDRSIZE + ( (risat) ? 0 : SIGLEN ) + ru_l->len + ( (isleqr) ? 0 : ru_r->len ); 
+	ru = (ltree_gist*)palloc( size );
+	ru->len = size;
+	ru->flag = 0;
+	if ( risat )
+		ru->flag |= LTG_ALLTRUE;
+	else
+		memcpy( (void*)LTG_SIGN(ru), rs, SIGLEN );
+	memcpy( (void*)LTG_LNODE(ru), (void*)ru_l, ru_l->len );
+	if ( isleqr )
+		ru->flag |= LTG_NORIGHT;
+	else
+		memcpy( (void*)LTG_RNODE(ru), (void*)ru_r, ru_r->len );
+
+	pfree(array);
+	v->spl_ldatum = PointerGetDatum(lu);
+	v->spl_rdatum = PointerGetDatum(ru);
+
+	PG_RETURN_POINTER(v);
+}
+
+static bool
+gist_isparent(ltree_gist *key, ltree *query) {
+	int4    numlevel = query->numlevel;
+	int	i;
+
+	for(i=query->numlevel;i>=0;i--) {
+		query->numlevel=i;
+		if ( ltree_compare(query,LTG_GETLNODE(key)) >=0 && ltree_compare(query,LTG_GETRNODE(key)) <= 0 ) {
+			query->numlevel = numlevel;
+			return true;
+		}
+	}
+
+	query->numlevel = numlevel;
+	return false;
+}
+
+static bool
+gist_ischild(ltree_gist *key, ltree *query) {
+	ltree	*left = LTG_GETLNODE(key);
+	ltree	*right = LTG_GETRNODE(key);
+	int4    numlevelL = left->numlevel;
+	int4    numlevelR = right->numlevel;
+	bool res = true;
+
+	if ( numlevelL > query->numlevel )
+		left->numlevel = query->numlevel;
+
+	if ( ltree_compare(query,left) < 0 )
+		res = false;
+
+	if ( numlevelR > query->numlevel )
+		right->numlevel = query->numlevel;
+
+	if ( res && ltree_compare(query,right) > 0 )
+		res = false;
+
+	left->numlevel = numlevelL;
+	right->numlevel = numlevelR;
+	return res;
+}
+
+static bool
+gist_qe(ltree_gist *key, lquery* query) {
+	lquery_level	*curq = LQUERY_FIRST(query);
+	BITVECP	sign = LTG_SIGN(key);
+	int	qlen = query->numlevel;
+
+	if ( LTG_ISALLTRUE(key) )
+		return true;
+
+	while( qlen>0 ) {
+		if ( curq->numvar && LQL_CANLOOKSIGN(curq) ) {
+			bool isexist=false;
+			int vlen = curq->numvar;
+			lquery_variant *curv = LQL_FIRST(curq);
+			while( vlen>0 ) {
+				if ( GETBIT( sign, HASHVAL( curv->val ) ) ) {
+					isexist=true;
+					break;
+				}
+				curv = LVAR_NEXT(curv);
+				vlen--;
+			}
+			if ( !isexist )
+				return false;	
+		}
+
+		curq = LQL_NEXT(curq);
+		qlen--;
+	}
+
+	return true;
+}
+
+static int
+gist_tqcmp(ltree* t, lquery* q) {
+	ltree_level *al = LTREE_FIRST(t);
+	lquery_level *ql = LQUERY_FIRST(q);
+	lquery_variant *bl;
+	int     an = t->numlevel;
+	int     bn = q->firstgood;
+	int     res = 0;
+
+	while( an>0 && bn>0 ) {
+		bl = LQL_FIRST(ql);
+		if ( (res = strncmp( al->name, bl->name, min(al->len, bl->len))) == 0 ) {
+			if ( al->len != bl->len )
+				return al->len - bl->len;
+		} else
+			return res;
+		an--; bn--;
+		al = LEVEL_NEXT(al);
+		ql = LQL_NEXT(ql);
+	}
+
+	return t->numlevel - q->firstgood;
+}
+
+static bool
+gist_between(ltree_gist *key, lquery* query) {
+	ltree	*left = LTG_GETLNODE(key);
+	ltree	*right = LTG_GETRNODE(key);
+	int4    numlevelL = left->numlevel;
+	int4    numlevelR = right->numlevel;
+	bool res = true;
+
+	if ( query->firstgood == 0 )
+		return true;
+
+	if ( numlevelL > query->firstgood )
+		left->numlevel = query->firstgood;
+
+	if ( gist_tqcmp(left,query) > 0 )
+		res = false;
+
+	if ( numlevelR > query->firstgood )
+		right->numlevel = query->firstgood;
+
+	if ( res && gist_tqcmp(right,query) < 0 )
+		res = false;
+
+	left->numlevel = numlevelL;
+	right->numlevel = numlevelR;
+	return res;
+}
+
+static bool
+checkcondition_bit(void *checkval, ITEM* val ) {
+	return ( FLG_CANLOOKSIGN(val->flag) ) ? GETBIT( checkval, HASHVAL( val->val ) ) : true;
+}
+
+static bool
+gist_qtxt(ltree_gist *key, ltxtquery* query) {
+	if ( LTG_ISALLTRUE(key) )
+		return true;
+ 
+	return execute(
+		GETQUERY(query),
+		(void*)LTG_SIGN(key), false,
+		checkcondition_bit
+	);
+}
+
+
+Datum   
+ltree_consistent(PG_FUNCTION_ARGS) {
+	GISTENTRY *entry = (GISTENTRY*)PG_GETARG_POINTER(0);
+	char *query = (char*)DatumGetPointer( PG_DETOAST_DATUM(PG_GETARG_DATUM(1)) );
+	ltree_gist *key = (ltree_gist*)DatumGetPointer( entry->key );
+	StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
+	bool res = false;
+
+#ifndef assert_enabled 
+#define assert_enabled 0
+#endif
+	
+	switch( strategy ) {
+		case BTLessStrategyNumber:
+			res = ( GIST_LEAF( entry ) ) ?
+					( ltree_compare((ltree*)query,LTG_NODE(key)) > 0 )
+				:
+					( ltree_compare((ltree*)query,LTG_GETLNODE(key)) >= 0 );
+			break;
+		case BTLessEqualStrategyNumber:
+			res = ( ltree_compare((ltree*)query,LTG_GETLNODE(key)) >= 0 );
+			break;
+		case BTEqualStrategyNumber:
+			if ( GIST_LEAF( entry ) )
+				res = ( ltree_compare((ltree*)query,LTG_NODE(key)) == 0 );
+			else
+				res = (
+					ltree_compare((ltree*)query,LTG_GETLNODE(key)) >= 0
+					&&
+					ltree_compare((ltree*)query,LTG_GETRNODE(key)) <= 0
+				);
+			break;
+		case BTGreaterEqualStrategyNumber:
+			res = ( ltree_compare((ltree*)query,LTG_GETRNODE(key)) <= 0 );
+			break;
+		case BTGreaterStrategyNumber:
+			res = ( GIST_LEAF( entry ) ) ?
+					( ltree_compare((ltree*)query,LTG_GETRNODE(key)) < 0 )
+				:
+					( ltree_compare((ltree*)query,LTG_GETRNODE(key)) <= 0 );
+			break;
+		case 10:
+			res = ( GIST_LEAF( entry ) ) ?
+					inner_isparent( (ltree*)query, LTG_NODE(key) )
+				:
+					gist_isparent( key, (ltree*)query);
+			break;
+		case 11:
+			res = ( GIST_LEAF( entry ) ) ?
+					inner_isparent( LTG_NODE(key), (ltree*)query)
+				:
+					gist_ischild( key, (ltree*)query);
+			break;
+		case 12:
+		case 13:
+			if ( GIST_LEAF( entry ) ) 
+				res = DatumGetBool( DirectFunctionCall2( ltq_regex,
+					 PointerGetDatum( LTG_NODE(key) ),
+					 PointerGetDatum( (lquery*)query )
+					) );
+			else 
+				res = ( gist_qe(key, (lquery*)query) && gist_between(key, (lquery*)query) );
+			break; 
+		case 14:
+		case 15:
+			if ( GIST_LEAF( entry ) ) 
+				res = DatumGetBool( DirectFunctionCall2( ltxtq_exec,
+					 PointerGetDatum( LTG_NODE(key) ),
+					 PointerGetDatum( (lquery*)query )
+					) );
+			else 
+				res = gist_qtxt(key, (ltxtquery*)query);
+			break;	
+		default:
+			elog(ERROR,"Unknown StrategyNumber: %d", strategy);
+	}
+	PG_RETURN_BOOL(res);
+}
+
--- a/contrib/ltree/ltree_io.c
+++ b/contrib/ltree/ltree_io.c
@ -0,0 +1,433 @@
+/*
+ * in/out function for ltree and lquery
+ * Teodor Sigaev <teodor@stack.net>
+ */
+
+#include "ltree.h"
+#include <ctype.h>
+#include "crc32.h" 
+
+PG_FUNCTION_INFO_V1(ltree_in);
+Datum ltree_in(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1(ltree_out);
+Datum ltree_out(PG_FUNCTION_ARGS);
+
+PG_FUNCTION_INFO_V1(lquery_in);
+Datum lquery_in(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1(lquery_out);
+Datum lquery_out(PG_FUNCTION_ARGS);
+
+
+#define UNCHAR elog(ERROR,"Syntax error in position %d near '%c'", ptr-buf, *ptr)
+
+typedef struct {
+	char* 	start;
+	int	len;
+	int	flag;
+} nodeitem;
+
+#define LTPRS_WAITNAME	0
+#define LTPRS_WAITDELIM	1
+
+Datum 
+ltree_in(PG_FUNCTION_ARGS) {
+	char    *buf = (char *) PG_GETARG_POINTER(0);
+	char	*ptr;
+	nodeitem *list, *lptr; 
+	int num=0, totallen = 0;
+	int state = LTPRS_WAITNAME;
+	ltree	*result;
+	ltree_level	*curlevel;
+
+	ptr=buf;
+	while( *ptr ) {
+		if ( *ptr == '.' )
+			num++;
+		ptr++;
+	}
+
+	list = lptr = (nodeitem*) palloc( sizeof(nodeitem)*(num+1) );
+	ptr=buf;
+	while( *ptr ) {
+		if ( state == LTPRS_WAITNAME ) {
+			if ( ISALNUM(*ptr) ) {
+				lptr->start = ptr;
+				state = LTPRS_WAITDELIM;
+			} else
+				UNCHAR;
+		} else if ( state == LTPRS_WAITDELIM ) {
+			if ( *ptr == '.' ) {
+				lptr->len = ptr - lptr->start;
+				if ( lptr->len > 255 ) 
+					elog(ERROR,"Name of level is too long (%d, must be < 256) in position %d", 
+						lptr->len, lptr->start - buf);
+				totallen += lptr->len + LEVEL_HDRSIZE;
+				lptr++;
+				state = LTPRS_WAITNAME;
+			} else if ( !ISALNUM(*ptr) )
+				UNCHAR;
+		} else
+			elog(ERROR,"Inner error in parser");
+		ptr++;
+	}
+
+	if ( state == LTPRS_WAITDELIM ) {
+		lptr->len = ptr - lptr->start;
+		if ( lptr->len > 255 ) 
+			elog(ERROR,"Name of level is too long (%d, must be < 256) in position %d", 
+				lptr->len, lptr->start - buf);
+		totallen += lptr->len + LEVEL_HDRSIZE;
+		lptr++;
+	} else if ( ! (state == LTPRS_WAITNAME && lptr == list) )
+		elog(ERROR,"Unexpected end of line");
+
+	result = (ltree*)palloc( LTREE_HDRSIZE + totallen );
+	result->len = LTREE_HDRSIZE + totallen;
+	result->numlevel = lptr-list;
+	curlevel = LTREE_FIRST(result);
+	lptr=list;
+	while( lptr-list < result->numlevel ) {
+		curlevel->len = (uint8) lptr->len;
+		memcpy( curlevel->name, lptr->start, lptr->len);
+		curlevel = LEVEL_NEXT(curlevel); 
+		lptr++;
+	}
+
+	pfree(list);
+
+	PG_RETURN_POINTER(result);
+}
+
+Datum 
+ltree_out(PG_FUNCTION_ARGS) {
+	ltree *in = PG_GETARG_LTREE(0);
+	char *buf,*ptr;
+	int i;
+	ltree_level     *curlevel;
+	
+	ptr = buf = (char*)palloc( in->len );
+	curlevel = LTREE_FIRST(in);
+	for(i=0;i<in->numlevel;i++) {
+		if ( i!=0 ) {
+			*ptr = '.';
+			ptr++;
+		}
+		memcpy( ptr, curlevel->name, curlevel->len );
+		ptr+=curlevel->len;
+		curlevel = LEVEL_NEXT(curlevel);
+	}
+
+	*ptr='\0';
+	PG_FREE_IF_COPY(in,0);
+
+	PG_RETURN_POINTER(buf);
+}
+
+#define LQPRS_WAITLEVEL	0
+#define LQPRS_WAITDELIM	1
+#define	LQPRS_WAITOPEN	2
+#define	LQPRS_WAITFNUM	3
+#define	LQPRS_WAITSNUM	4
+#define	LQPRS_WAITND	5
+#define LQPRS_WAITCLOSE	6
+#define LQPRS_WAITEND	7
+#define LQPRS_WAITVAR	8
+
+
+#define GETVAR(x) ( *((nodeitem**)LQL_FIRST(x)) )  
+
+Datum 
+lquery_in(PG_FUNCTION_ARGS) {
+	char    *buf = (char *) PG_GETARG_POINTER(0);
+	char	*ptr;
+	int num=0, totallen = 0, numOR=0;
+	int state = LQPRS_WAITLEVEL;
+	lquery	*result;
+	nodeitem  *lptr=NULL;
+	lquery_level	*cur,*curqlevel, *tmpql;
+	lquery_variant	*lrptr=NULL;
+	bool hasnot=false;
+	bool wasbad=false;
+
+	ptr=buf;
+	while( *ptr ) {
+		if ( *ptr == '.' )
+			num++;
+		else if ( *ptr == '|' )
+			numOR++;
+		ptr++;
+	}
+	
+	num++;
+	curqlevel = tmpql = (lquery_level*) palloc( ( LQL_HDRSIZE+sizeof(nodeitem*) )*(num) );
+	memset((void*)tmpql,0, ( LQL_HDRSIZE+sizeof(nodeitem*) )*(num) );
+	ptr=buf;
+	while( *ptr ) {
+		if ( state==LQPRS_WAITLEVEL ) {
+			if ( ISALNUM(*ptr) ) {
+				GETVAR(curqlevel) = lptr = (nodeitem*)palloc( sizeof(nodeitem)*(numOR+1) );
+				memset((void*)GETVAR(curqlevel),  0,sizeof(nodeitem)*(numOR+1) );
+				lptr->start = ptr;
+				state = LQPRS_WAITDELIM;
+				curqlevel->numvar = 1;
+			} else if ( *ptr == '!' ) {
+				GETVAR(curqlevel) = lptr = (nodeitem*)palloc( sizeof(nodeitem)*(numOR+1) );
+				memset((void*)GETVAR(curqlevel),  0,sizeof(nodeitem)*(numOR+1) );
+				lptr->start = ptr+1;
+				state = LQPRS_WAITDELIM;
+				curqlevel->numvar = 1;
+				curqlevel->flag |= LQL_NOT;
+				hasnot=true;
+			} else if ( *ptr == '*' ) {
+				state = LQPRS_WAITOPEN;
+			} else
+				UNCHAR;
+		} else if ( state==LQPRS_WAITVAR ) {
+			if ( ISALNUM(*ptr) ) {
+				lptr++;
+				lptr->start = ptr;
+				state = LQPRS_WAITDELIM;
+				curqlevel->numvar++;
+			} else
+				UNCHAR;
+		} else if ( state==LQPRS_WAITDELIM ) {
+			if ( *ptr == '@' ) {
+				if ( lptr->start == ptr )
+					UNCHAR;
+				lptr->flag |= LVAR_INCASE;
+				curqlevel->flag |= LVAR_INCASE;
+			} else if ( *ptr == '*' ) {
+				if ( lptr->start == ptr )
+					UNCHAR;
+				lptr->flag |= LVAR_ANYEND;
+				curqlevel->flag |= LVAR_ANYEND;
+			} else if ( *ptr == '%' ) {
+				if ( lptr->start == ptr )
+					UNCHAR;
+				lptr->flag |= LVAR_SUBLEXEM;
+				curqlevel->flag |= LVAR_SUBLEXEM;
+			} else if ( *ptr == '|' ) {
+				lptr->len = ptr - lptr->start - 
+					( ( lptr->flag & LVAR_SUBLEXEM ) ? 1 : 0 ) - 
+					( ( lptr->flag & LVAR_INCASE ) ? 1 : 0 ) - 
+					( ( lptr->flag & LVAR_ANYEND ) ? 1 : 0 );
+				if ( lptr->len > 255 ) 
+					elog(ERROR,"Name of level is too long (%d, must be < 256) in position %d", 
+						lptr->len, lptr->start - buf);
+				state = LQPRS_WAITVAR;
+			} else if ( *ptr == '.' ) {
+				lptr->len = ptr - lptr->start - 
+					( ( lptr->flag & LVAR_SUBLEXEM ) ? 1 : 0 ) - 
+					( ( lptr->flag & LVAR_INCASE ) ? 1 : 0 ) - 
+					( ( lptr->flag & LVAR_ANYEND ) ? 1 : 0 );
+				if ( lptr->len > 255 ) 
+					elog(ERROR,"Name of level is too long (%d, must be < 256) in position %d", 
+						lptr->len, lptr->start - buf);
+				state = LQPRS_WAITLEVEL;
+				curqlevel++;
+			} else if ( ISALNUM(*ptr) ) {
+				if ( lptr->flag )
+					UNCHAR;
+			} else
+				UNCHAR;
+		} else if ( state == LQPRS_WAITOPEN ) {
+			if ( *ptr == '{' ) {
+				state = LQPRS_WAITFNUM;
+			} else if ( *ptr == '.' ) {
+				curqlevel->low=0;
+				curqlevel->high=0xffff;
+				curqlevel++;
+				state = LQPRS_WAITLEVEL;
+			} else
+				UNCHAR;
+		} else if ( state == LQPRS_WAITFNUM ) {
+			if ( *ptr == ',' ) {
+				state = LQPRS_WAITSNUM; 
+			} else if ( isdigit(*ptr) ) {
+				curqlevel->low = atoi( ptr );
+				state = LQPRS_WAITND;
+			} else
+				UNCHAR; 
+		} else if ( state == LQPRS_WAITSNUM ) {
+			if ( isdigit(*ptr) ) {
+				curqlevel->high = atoi( ptr );
+				state =  LQPRS_WAITCLOSE;
+			} else if ( *ptr == '}' ) {
+				curqlevel->high = 0xffff;
+				state = LQPRS_WAITEND;
+			} else
+				UNCHAR;
+		} else if ( state == LQPRS_WAITCLOSE ) {
+			if ( *ptr == '}' )
+				state = LQPRS_WAITEND;
+			else if ( !isdigit(*ptr) )
+				UNCHAR;
+		} else if ( state == LQPRS_WAITND ) { 
+			if ( *ptr == '}' ) {
+				curqlevel->high = curqlevel->low;
+				state = LQPRS_WAITEND;
+			} else if ( *ptr == ',' )
+				state = LQPRS_WAITSNUM;
+			else if ( !isdigit(*ptr) )
+				UNCHAR;
+		} else if ( state == LQPRS_WAITEND ) {
+			if ( *ptr == '.' ) {
+				state = LQPRS_WAITLEVEL;
+				curqlevel++;
+			} else
+				UNCHAR;
+		} else
+			elog(ERROR,"Inner error in parser");
+		ptr++;
+	}
+			
+	if ( state==LQPRS_WAITDELIM ) {
+		if ( lptr->start == ptr )
+			elog(ERROR,"Unexpected end of line");
+		lptr->len = ptr - lptr->start -
+			( ( lptr->flag & LVAR_SUBLEXEM ) ? 1 : 0 ) - 
+			( ( lptr->flag & LVAR_INCASE ) ? 1 : 0 ) - 
+			( ( lptr->flag & LVAR_ANYEND ) ? 1 : 0 );
+		if ( lptr->len==0 )
+			elog(ERROR,"Unexpected end of line");
+		if ( lptr->len > 255 ) 
+			elog(ERROR,"Name of level is too long (%d, must be < 256) in position %d", 
+				lptr->len, lptr->start - buf);
+	} else if ( state == LQPRS_WAITOPEN ) {
+		curqlevel->high = 0xffff;
+	} else if ( state != LQPRS_WAITEND ) 
+		elog(ERROR,"Unexpected end of line");
+		 
+	curqlevel = tmpql;
+	totallen = LQUERY_HDRSIZE; 
+	while( curqlevel-tmpql < num ) {
+		totallen += LQL_HDRSIZE; 
+		if ( curqlevel->numvar ) {
+			lptr = GETVAR(curqlevel);
+			while( lptr-GETVAR(curqlevel) < curqlevel->numvar ) {
+				totallen += LVAR_HDRSIZE + lptr->len;
+				lptr++;
+			}
+		} else if ( curqlevel->low > curqlevel->high )
+			elog(ERROR,"Low limit(%d) is greater than upper(%d)",curqlevel->low,curqlevel->high ); 
+		curqlevel++;
+	}
+	
+	result = (lquery*)palloc( totallen );
+	result->len = totallen;
+	result->numlevel = num;
+	result->firstgood = 0;
+	result->flag=0;
+	if ( hasnot )
+		result->flag |= LQUERY_HASNOT;
+	cur = LQUERY_FIRST(result);
+	curqlevel = tmpql;
+	while( curqlevel-tmpql < num ) {
+		memcpy(cur,curqlevel,LQL_HDRSIZE);
+		cur->totallen=LQL_HDRSIZE;
+		if ( curqlevel->numvar ) {
+			lrptr = LQL_FIRST(cur);
+			lptr = GETVAR(curqlevel);
+			while( lptr-GETVAR(curqlevel) < curqlevel->numvar ) {
+				cur->totallen += LVAR_HDRSIZE + lptr->len;
+				lrptr->len  = lptr->len;
+				lrptr->flag = lptr->flag;
+				lrptr->val = crc32_sz((uint8 *) lptr->start, lptr->len);
+				memcpy( lrptr->name, lptr->start, lptr->len);
+				lptr++;
+				lrptr = LVAR_NEXT( lrptr );
+			}
+			pfree( GETVAR(curqlevel) );
+			if ( cur->numvar > 1 || cur->flag != 0 )
+				wasbad=true;
+			else if ( wasbad==false )
+				(result->firstgood)++;   
+		} else
+			wasbad=true;
+		curqlevel++;
+		cur = LQL_NEXT(cur);
+	}
+
+	pfree(tmpql);
+	PG_RETURN_POINTER(result);
+}
+
+Datum 
+lquery_out(PG_FUNCTION_ARGS) {
+	lquery *in = PG_GETARG_LQUERY(0);
+	char *buf,*ptr;
+	int i,j,totallen=0;
+	lquery_level     *curqlevel;
+	lquery_variant     *curtlevel;
+
+	curqlevel = LQUERY_FIRST(in);
+	for(i=0;i<in->numlevel;i++) {
+		if ( curqlevel->numvar )
+			totallen = (curqlevel->numvar*4) + 1 + curqlevel->totallen;
+		else
+			totallen = 2*11 + 4;
+		totallen++;
+		curqlevel = LQL_NEXT(curqlevel);
+	}
+	
+	
+	ptr = buf = (char*)palloc( totallen );
+	curqlevel = LQUERY_FIRST(in);
+	for(i=0;i<in->numlevel;i++) {
+		if ( i!=0 ) {
+			*ptr = '.';
+			ptr++;
+		}
+		if ( curqlevel->numvar ) {
+			if ( curqlevel->flag & LQL_NOT ) {
+				*ptr = '!';
+				ptr++;
+			}
+			curtlevel = LQL_FIRST(curqlevel);
+			for(j=0;j<curqlevel->numvar;j++) {
+				if ( j!=0 ) {
+					*ptr = '|';
+					ptr++;
+				}
+				memcpy( ptr, curtlevel->name, curtlevel->len );
+				ptr+=curtlevel->len;
+				if ( (curtlevel->flag & LVAR_SUBLEXEM) ) {
+					*ptr = '%';
+					ptr++;
+				}
+				if ( (curtlevel->flag & LVAR_INCASE) ) {
+					*ptr = '@';
+					ptr++;
+				}
+				if ( (curtlevel->flag & LVAR_ANYEND) ) {
+					*ptr = '*';
+					ptr++;
+				}
+				curtlevel = LVAR_NEXT(curtlevel);
+			}
+		} else {
+			if ( curqlevel->low == curqlevel->high ) {
+				sprintf(ptr,"*{%d}",curqlevel->low);
+			} else if ( curqlevel->low == 0 ) {
+				if ( curqlevel->high == 0xffff ) {
+					*ptr='*';
+					*(ptr+1)='\0';
+				} else
+					sprintf(ptr,"*{,%d}",curqlevel->high);
+			} else if ( curqlevel->high == 0xffff ) {
+				sprintf(ptr,"*{%d,}",curqlevel->low);
+			} else 
+				sprintf(ptr,"*{%d,%d}", curqlevel->low, curqlevel->high);
+			ptr = strchr(ptr,'\0');
+		}
+
+		curqlevel = LQL_NEXT(curqlevel);
+	}
+
+	*ptr='\0';
+	PG_FREE_IF_COPY(in,0);
+
+	PG_RETURN_POINTER(buf);
+}
+
+
--- a/contrib/ltree/ltree_op.c
+++ b/contrib/ltree/ltree_op.c
@ -0,0 +1,310 @@
+/*
+ * op function for ltree 
+ * Teodor Sigaev <teodor@stack.net>
+ */
+
+#include "ltree.h"
+#include <ctype.h>
+
+/* compare functions */
+PG_FUNCTION_INFO_V1(ltree_cmp);
+PG_FUNCTION_INFO_V1(ltree_lt);
+PG_FUNCTION_INFO_V1(ltree_le);
+PG_FUNCTION_INFO_V1(ltree_eq);
+PG_FUNCTION_INFO_V1(ltree_ne);
+PG_FUNCTION_INFO_V1(ltree_ge);
+PG_FUNCTION_INFO_V1(ltree_gt);
+PG_FUNCTION_INFO_V1(nlevel);
+PG_FUNCTION_INFO_V1(ltree_isparent);
+PG_FUNCTION_INFO_V1(ltree_risparent);
+PG_FUNCTION_INFO_V1(subltree);
+PG_FUNCTION_INFO_V1(subpath);
+PG_FUNCTION_INFO_V1(ltree_addltree);
+PG_FUNCTION_INFO_V1(ltree_addtext);
+PG_FUNCTION_INFO_V1(ltree_textadd);
+Datum   ltree_cmp(PG_FUNCTION_ARGS);
+Datum   ltree_lt(PG_FUNCTION_ARGS);
+Datum   ltree_le(PG_FUNCTION_ARGS);
+Datum   ltree_eq(PG_FUNCTION_ARGS);
+Datum   ltree_ne(PG_FUNCTION_ARGS);
+Datum   ltree_ge(PG_FUNCTION_ARGS);
+Datum   ltree_gt(PG_FUNCTION_ARGS);
+Datum   nlevel(PG_FUNCTION_ARGS);
+Datum   subltree(PG_FUNCTION_ARGS);
+Datum   subpath(PG_FUNCTION_ARGS);
+Datum   ltree_addltree(PG_FUNCTION_ARGS);
+Datum   ltree_addtext(PG_FUNCTION_ARGS);
+Datum   ltree_textadd(PG_FUNCTION_ARGS);
+
+int
+ltree_compare(const ltree *a, const ltree *b) {
+	ltree_level *al = LTREE_FIRST(a);
+	ltree_level *bl = LTREE_FIRST(b);
+	int	an = a->numlevel;
+	int	bn = b->numlevel;
+	int 	res = 0;
+
+	while( an>0 && bn>0 ) {
+		if ( (res = strncmp( al->name, bl->name, min(al->len, bl->len))) == 0 ) {
+			if ( al->len != bl->len )
+				return (al->len - bl->len)*10*(an+1);
+		} else
+			return res*10*(an+1);
+
+		an--; bn--;
+		al = LEVEL_NEXT(al); 
+		bl = LEVEL_NEXT(bl); 
+	}
+
+	return (a->numlevel - b->numlevel)*10*(an+1);
+} 
+
+#define RUNCMP 						\
+ltree *a	= PG_GETARG_LTREE(0);			\
+ltree *b	= PG_GETARG_LTREE(1);			\
+int res = ltree_compare(a,b);				\
+PG_FREE_IF_COPY(a,0);					\
+PG_FREE_IF_COPY(b,1);					\
+
+Datum
+ltree_cmp(PG_FUNCTION_ARGS) {
+	RUNCMP
+	PG_RETURN_INT32(res);
+}
+
+Datum
+ltree_lt(PG_FUNCTION_ARGS) {
+	RUNCMP
+	PG_RETURN_BOOL( (res<0) ? true : false );
+}
+
+Datum
+ltree_le(PG_FUNCTION_ARGS) {
+	RUNCMP
+	PG_RETURN_BOOL( (res<=0) ? true : false );
+}
+
+Datum
+ltree_eq(PG_FUNCTION_ARGS) {
+	RUNCMP
+	PG_RETURN_BOOL( (res==0) ? true : false );
+}
+
+Datum
+ltree_ge(PG_FUNCTION_ARGS) {
+	RUNCMP
+	PG_RETURN_BOOL( (res>=0) ? true : false );
+}
+
+Datum
+ltree_gt(PG_FUNCTION_ARGS) {
+	RUNCMP
+	PG_RETURN_BOOL( (res>0) ? true : false );
+}
+
+Datum
+ltree_ne(PG_FUNCTION_ARGS) {
+	RUNCMP
+	PG_RETURN_BOOL( (res!=0) ? true : false );
+}
+
+Datum
+nlevel(PG_FUNCTION_ARGS) {
+	ltree *a	= PG_GETARG_LTREE(0);
+	int res = a->numlevel;
+	PG_FREE_IF_COPY(a,0);
+	PG_RETURN_INT32(res);
+}
+
+bool
+inner_isparent(const ltree *c, const ltree *p) {
+	ltree_level *cl = LTREE_FIRST(c);
+	ltree_level *pl = LTREE_FIRST(p);
+	int	pn = p->numlevel;
+
+	if ( pn > c->numlevel )
+		return false;
+
+	while( pn>0 ) {
+		if ( cl->len != pl->len )
+			return false;
+		if ( strncmp( cl->name, pl->name, cl->len ) )
+			return false;
+
+		pn--;
+		cl = LEVEL_NEXT(cl); 
+		pl = LEVEL_NEXT(pl); 
+	}
+	return true;
+}
+
+Datum   
+ltree_isparent(PG_FUNCTION_ARGS) {
+	ltree *c	= PG_GETARG_LTREE(1);
+	ltree *p	= PG_GETARG_LTREE(0);
+	bool res = inner_isparent(c,p);
+	PG_FREE_IF_COPY(c,1);
+	PG_FREE_IF_COPY(p,0);
+	PG_RETURN_BOOL( res );
+}
+
+Datum   
+ltree_risparent(PG_FUNCTION_ARGS) {
+	ltree *c	= PG_GETARG_LTREE(0);
+	ltree *p	= PG_GETARG_LTREE(1);
+	bool res = inner_isparent(c,p);
+	PG_FREE_IF_COPY(c,0);
+	PG_FREE_IF_COPY(p,1);
+	PG_RETURN_BOOL( res );
+}
+
+
+static ltree*
+inner_subltree(ltree *t, int4 startpos, int4 endpos) {
+	char *start=NULL,*end=NULL;
+	ltree_level *ptr = LTREE_FIRST(t);
+	ltree	*res;
+	int i;
+
+	if ( startpos <0 || endpos <0 || startpos>=t->numlevel || startpos >= endpos )
+		elog(ERROR,"Wrong positions");
+
+	if ( endpos > t->numlevel )
+		endpos = t->numlevel;
+
+	for(i=0;i<endpos ;i++) {
+		if ( i==startpos )
+			start = (char*)ptr;
+		if ( i==endpos-1 ) {
+			end = (char*)LEVEL_NEXT(ptr);
+			break;
+		}
+		ptr = LEVEL_NEXT(ptr); 
+	}
+
+	res=(ltree*)palloc( LTREE_HDRSIZE + (end-start) );
+	res->len = LTREE_HDRSIZE + (end-start);
+	res->numlevel = endpos-startpos;
+
+	memcpy( LTREE_FIRST(res), start, end-start);	
+	
+	return res;
+}
+
+Datum
+subltree(PG_FUNCTION_ARGS) {
+	ltree *t = PG_GETARG_LTREE(0);
+	ltree *res = inner_subltree(t,PG_GETARG_INT32(1),PG_GETARG_INT32(2));
+
+	PG_FREE_IF_COPY(t,0);
+	PG_RETURN_POINTER(res);
+}
+
+Datum   
+subpath(PG_FUNCTION_ARGS) {
+	ltree *t = PG_GETARG_LTREE(0);
+	int4 start = PG_GETARG_INT32(1);
+	int4 len   = ( fcinfo->nargs==3 ) ? PG_GETARG_INT32(2) : 0;
+	int4 end;
+	ltree *res;
+
+	end = start+len;
+
+	if ( start < 0 ) { 
+		start = t->numlevel + start;
+		end = start+len;
+	}
+	if ( start < 0 ) { /* start > t->numlevel */ 
+		start = t->numlevel + start;
+		end = start+len;
+	}
+
+	if ( len < 0 )
+		end = t->numlevel + len;
+	else if ( len == 0 )
+		end = 0xffff;
+
+	res = inner_subltree(t,start,end);
+
+	PG_FREE_IF_COPY(t,0);
+	PG_RETURN_POINTER(res);
+} 
+
+static ltree*
+ltree_concat( ltree *a, ltree *b) {
+	ltree *r;
+	r=(ltree*)palloc( a->len + b->len - LTREE_HDRSIZE);
+        r->len = a->len + b->len - LTREE_HDRSIZE;
+        r->numlevel = a->numlevel + b->numlevel;
+
+        memcpy( LTREE_FIRST(r), LTREE_FIRST(a), a->len - LTREE_HDRSIZE);
+        memcpy( ((char*)LTREE_FIRST(r))+ a->len - LTREE_HDRSIZE, LTREE_FIRST(b), b->len -
+ LTREE_HDRSIZE);
+    return r;
+}
+
+Datum 
+ltree_addltree(PG_FUNCTION_ARGS) {
+	ltree *a = PG_GETARG_LTREE(0);
+	ltree *b = PG_GETARG_LTREE(1);
+	ltree *r;
+
+	r = ltree_concat(a, b);
+	PG_FREE_IF_COPY(a,0);
+	PG_FREE_IF_COPY(b,1);
+	PG_RETURN_POINTER(r);
+}
+
+Datum
+ltree_addtext(PG_FUNCTION_ARGS) {
+	ltree *a = PG_GETARG_LTREE(0);
+	text *b = PG_GETARG_TEXT_P(1);
+	char *s;
+	ltree *r,*tmp;
+
+	s = (char*)palloc( VARSIZE(b) - VARHDRSZ+1 );
+	memcpy(s, VARDATA(b), VARSIZE(b) - VARHDRSZ );
+	s[VARSIZE(b) - VARHDRSZ] = '\0';
+
+	tmp = (ltree*)DatumGetPointer( DirectFunctionCall1( 
+		ltree_in,
+		PointerGetDatum(s)
+	) );
+
+	pfree(s);
+
+	r = ltree_concat(a,tmp);
+
+	pfree( tmp );
+	
+	PG_FREE_IF_COPY(a,0);
+	PG_FREE_IF_COPY(b,1);
+	PG_RETURN_POINTER(r);
+}
+
+Datum
+ltree_textadd(PG_FUNCTION_ARGS) {
+        ltree *a = PG_GETARG_LTREE(1);
+        text *b = PG_GETARG_TEXT_P(0);
+        char *s;
+        ltree *r,*tmp;
+
+        s = (char*)palloc( VARSIZE(b) - VARHDRSZ + 1 );
+        memcpy(s, VARDATA(b), VARSIZE(b) - VARHDRSZ );
+        s[VARSIZE(b) - VARHDRSZ] = '\0';
+       
+        tmp = (ltree*)DatumGetPointer( DirectFunctionCall1(
+                ltree_in,
+                PointerGetDatum(s)
+        ) );
+
+        pfree(s);
+
+        r = ltree_concat(tmp,a);
+
+        pfree( tmp );
+       
+        PG_FREE_IF_COPY(a,1);
+        PG_FREE_IF_COPY(b,0);
+        PG_RETURN_POINTER(r);
+}
--- a/contrib/ltree/ltreetest.sql
+++ b/contrib/ltree/ltreetest.sql
@ -0,0 +1,16 @@
+create table test ( path ltree);
+insert into test values ('Top');
+insert into test values ('Top.Science');
+insert into test values ('Top.Science.Astronomy');
+insert into test values ('Top.Science.Astronomy.Astrophysics');
+insert into test values ('Top.Science.Astronomy.Cosmology');
+insert into test values ('Top.Hobbies');
+insert into test values ('Top.Hobbies.Amateurs_Astronomy');
+insert into test values ('Top.Collections');
+insert into test values ('Top.Collections.Pictures');
+insert into test values ('Top.Collections.Pictures.Astronomy');
+insert into test values ('Top.Collections.Pictures.Astronomy.Stars');
+insert into test values ('Top.Collections.Pictures.Astronomy.Galaxies');
+insert into test values ('Top.Collections.Pictures.Astronomy.Astronauts');
+create index path_gist_idx on test using gist(path);
+create index path_idx on test using btree(path);
--- a/contrib/ltree/ltxtquery_io.c
+++ b/contrib/ltree/ltxtquery_io.c
@ -0,0 +1,484 @@
+/*
+ * txtquery io 
+ * Teodor Sigaev <teodor@stack.net>
+ */
+
+#include "ltree.h"
+#include <ctype.h>
+#include "crc32.h"
+
+PG_FUNCTION_INFO_V1(ltxtq_in);
+Datum	   ltxtq_in(PG_FUNCTION_ARGS);
+PG_FUNCTION_INFO_V1(ltxtq_out);
+Datum	   ltxtq_out(PG_FUNCTION_ARGS);
+
+
+/* parser's states */
+#define WAITOPERAND 1
+#define INOPERAND 2
+#define WAITOPERATOR    3
+
+/*
+ * node of query tree, also used
+ * for storing polish notation in parser
+ */
+typedef struct NODE {
+	int4	    type;
+	int4	    val;
+	int2	    distance;
+	int2	    length;
+	uint16	    flag;
+	struct NODE *next;
+}       NODE;
+
+typedef struct {
+	char       *buf;
+	int4	    state;
+	int4	    count;
+	/* reverse polish notation in list (for temprorary usage) */
+	NODE       *str;
+	/* number in str */
+	int4	    num;
+
+	/* user-friendly operand */
+	int4	    lenop;
+	int4	    sumlen;
+	char       *op;
+	char       *curop;
+}       QPRS_STATE;
+
+/*
+ * get token from query string
+ */
+static int4
+gettoken_query(QPRS_STATE * state, int4 *val, int4 *lenval, char **strval, uint16 *flag)
+{
+	while (1)
+	{
+		switch (state->state)
+		{
+			case WAITOPERAND:
+				if (*(state->buf) == '!')
+				{
+					(state->buf)++;
+					*val = (int4) '!';
+					return OPR;
+				}
+				else if (*(state->buf) == '(')
+				{
+					state->count++;
+					(state->buf)++;
+					return OPEN;
+				}
+				else if ( ISALNUM(*(state->buf)) )
+				{
+					state->state = INOPERAND;
+					*strval = state->buf;
+					*lenval = 1;
+					*flag = 0;
+				} else if ( !isspace(*(state->buf)) )
+					elog(ERROR,"Operand syntax error");
+				break;
+			case INOPERAND:
+				if ( ISALNUM(*(state->buf)) ) {
+					if ( *flag )
+						elog(ERROR,"Modificators syntax error");
+					(*lenval)++;
+				} else if ( *(state->buf) == '%' ) {
+					*flag |= LVAR_SUBLEXEM;
+				} else if ( *(state->buf) == '@' ) {
+					*flag |= LVAR_INCASE;
+				} else if ( *(state->buf) == '*' ) {
+					*flag |= LVAR_ANYEND;
+				} else {
+					state->state = WAITOPERATOR;
+					return VAL;
+				}
+				break;
+			case WAITOPERATOR:
+				if (*(state->buf) == '&' || *(state->buf) == '|')
+				{
+					state->state = WAITOPERAND;
+					*val = (int4) *(state->buf);
+					(state->buf)++;
+					return OPR;
+				}
+				else if (*(state->buf) == ')')
+				{
+					(state->buf)++;
+					state->count--;
+					return (state->count < 0) ? ERR : CLOSE;
+				}
+				else if (*(state->buf) == '\0')
+					return (state->count) ? ERR : END;
+				else if (*(state->buf) != ' ')
+					return ERR;
+				break;
+			default:
+				return ERR;
+				break;
+		}
+		(state->buf)++;
+	}
+	return END;
+}
+
+/*
+ * push new one in polish notation reverse view
+ */
+static void
+pushquery(QPRS_STATE * state, int4 type, int4 val, int4 distance, int4 lenval, uint16 flag)
+{
+	NODE       *tmp = (NODE *) palloc(sizeof(NODE));
+
+	tmp->type = type;
+	tmp->val = val;
+	tmp->flag = flag;
+	if (distance > 0xffff)
+		elog(ERROR, "Value is too big");
+	if (lenval > 0xff)
+		elog(ERROR, "Operand is too long");
+	tmp->distance = distance;
+	tmp->length = lenval;
+	tmp->next = state->str;
+	state->str = tmp;
+	state->num++;
+}
+
+/*
+ * This function is used for query_txt parsing
+ */
+static void
+pushval_asis(QPRS_STATE * state, int type, char *strval, int lenval, uint16 flag)
+{
+	if (lenval > 0xffff)
+		elog(ERROR, "Word is too long");
+
+	pushquery(state, type, crc32_sz((uint8 *) strval, lenval),
+			  state->curop - state->op, lenval, flag);
+
+	while (state->curop - state->op + lenval + 1 >= state->lenop)
+	{
+		int4	    tmp = state->curop - state->op;
+
+		state->lenop *= 2;
+		state->op = (char *) repalloc((void *) state->op, state->lenop);
+		state->curop = state->op + tmp;
+	}
+	memcpy((void *) state->curop, (void *) strval, lenval);
+	state->curop += lenval;
+	*(state->curop) = '\0';
+	state->curop++;
+	state->sumlen += lenval + 1;
+	return;
+}
+
+#define STACKDEPTH      32
+/*
+ * make polish notaion of query
+ */
+static int4
+makepol(QPRS_STATE * state)
+{
+	int4	    val,
+				type;
+	int4	    lenval;
+	char       *strval;
+	int4	    stack[STACKDEPTH];
+	int4	    lenstack = 0;
+	uint16	    flag;
+
+	while ((type = gettoken_query(state, &val, &lenval, &strval,&flag)) != END) {
+		switch (type)
+		{
+			case VAL:
+				pushval_asis(state, VAL, strval, lenval,flag);
+				while (lenstack && (stack[lenstack - 1] == (int4) '&' ||
+									stack[lenstack - 1] == (int4) '!'))
+				{
+					lenstack--;
+					pushquery(state, OPR, stack[lenstack], 0, 0, 0);
+				}
+				break;
+			case OPR:
+				if (lenstack && val == (int4) '|')
+					pushquery(state, OPR, val, 0, 0, 0);
+				else
+				{
+					if (lenstack == STACKDEPTH)
+						elog(ERROR, "Stack too short");
+					stack[lenstack] = val;
+					lenstack++;
+				}
+				break;
+			case OPEN:
+				if (makepol(state) == ERR)
+					return ERR;
+				if (lenstack && (stack[lenstack - 1] == (int4) '&' ||
+								 stack[lenstack - 1] == (int4) '!'))
+				{
+					lenstack--;
+					pushquery(state, OPR, stack[lenstack], 0, 0, 0);
+				}
+				break;
+			case CLOSE:
+				while (lenstack)
+				{
+					lenstack--;
+					pushquery(state, OPR, stack[lenstack], 0, 0, 0);
+				};
+				return END;
+				break;
+			case ERR:
+			default:
+				elog(ERROR, "Syntax error");
+				return ERR;
+
+		}
+	}
+	while (lenstack) {
+		lenstack--;
+		pushquery(state, OPR, stack[lenstack], 0, 0, 0);
+	};
+	return END;
+}
+
+static void
+findoprnd(ITEM * ptr, int4 *pos)
+{
+	if (ptr[*pos].type == VAL || ptr[*pos].type == VALTRUE)
+	{
+		ptr[*pos].left = 0;
+		(*pos)++;
+	}
+	else if (ptr[*pos].val == (int4) '!')
+	{
+		ptr[*pos].left = 1;
+		(*pos)++;
+		findoprnd(ptr, pos);
+	}
+	else
+	{
+		ITEM       *curitem = &ptr[*pos];
+		int4	    tmp = *pos;
+
+		(*pos)++;
+		findoprnd(ptr, pos);
+		curitem->left = *pos - tmp;
+		findoprnd(ptr, pos);
+	}
+}
+
+
+/*
+ * input
+ */
+static ltxtquery *
+queryin(char *buf)
+{
+	QPRS_STATE      state;
+	int4	    i;
+	ltxtquery  *query;
+	int4	    commonlen;
+	ITEM       *ptr;
+	NODE       *tmp;
+	int4	    pos = 0;
+
+#ifdef BS_DEBUG
+	char	    pbuf[16384],
+			   *cur;
+#endif
+
+	/* init state */
+	state.buf = buf;
+	state.state = WAITOPERAND;
+	state.count = 0;
+	state.num = 0;
+	state.str = NULL;
+
+	/* init list of operand */
+	state.sumlen = 0;
+	state.lenop = 64;
+	state.curop = state.op = (char *) palloc(state.lenop);
+	*(state.curop) = '\0';
+
+	/* parse query & make polish notation (postfix, but in reverse order) */
+	makepol(&state);
+	if (!state.num)
+		elog(ERROR, "Empty query");
+	/* make finish struct */
+	commonlen = COMPUTESIZE(state.num, state.sumlen);
+	query = (ltxtquery *) palloc(commonlen);
+	query->len = commonlen;
+	query->size = state.num;
+	ptr = GETQUERY(query);
+
+	/* set item in polish notation */
+	for (i = 0; i < state.num; i++)
+	{
+		ptr[i].type = state.str->type;
+		ptr[i].val = state.str->val;
+		ptr[i].distance = state.str->distance;
+		ptr[i].length = state.str->length;
+		ptr[i].flag = state.str->flag;
+		tmp = state.str->next;
+		pfree(state.str);
+		state.str = tmp;
+	}
+
+	/* set user friendly-operand view */
+	memcpy((void *) GETOPERAND(query), (void *) state.op, state.sumlen);
+	pfree(state.op);
+
+	/* set left operand's position for every operator */
+	pos = 0;
+	findoprnd(ptr, &pos);
+
+	return query;
+}
+
+/*
+ * in without morphology
+ */
+Datum
+ltxtq_in(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_POINTER(queryin((char *) PG_GETARG_POINTER(0)));
+}
+
+/*
+ * out function
+ */
+typedef struct
+{
+	ITEM       *curpol;
+	char       *buf;
+	char       *cur;
+	char       *op;
+	int4	    buflen;
+}       INFIX;
+
+#define RESIZEBUF(inf,addsize) \
+while( ( inf->cur - inf->buf ) + addsize + 1 >= inf->buflen ) \
+{ \
+	int4 len = inf->cur - inf->buf; \
+	inf->buflen *= 2; \
+	inf->buf = (char*) repalloc( (void*)inf->buf, inf->buflen ); \
+	inf->cur = inf->buf + len; \
+}
+
+/*
+ * recursive walk on tree and print it in
+ * infix (human-readable) view
+ */
+static void
+infix(INFIX * in, bool first)
+{
+	if (in->curpol->type == VAL)
+	{
+		char       *op = in->op + in->curpol->distance;
+
+		RESIZEBUF(in, in->curpol->length * 2 + 5);
+		while (*op) {
+			*(in->cur) = *op;
+			op++;
+			in->cur++;
+		}
+		if ( in->curpol->flag & LVAR_SUBLEXEM ) {
+			*(in->cur) = '%';
+			in->cur++;
+		}
+		if ( in->curpol->flag & LVAR_INCASE ) {
+			*(in->cur) = '@';
+			in->cur++;
+		}
+		if ( in->curpol->flag & LVAR_ANYEND ) {
+			*(in->cur) = '*';
+			in->cur++;
+		}
+		*(in->cur) = '\0';
+		in->curpol++;
+	}
+	else if (in->curpol->val == (int4) '!')
+	{
+		bool	    isopr = false;
+
+		RESIZEBUF(in, 1);
+		*(in->cur) = '!';
+		in->cur++;
+		*(in->cur) = '\0';
+		in->curpol++;
+		if (in->curpol->type == OPR)
+		{
+			isopr = true;
+			RESIZEBUF(in, 2);
+			sprintf(in->cur, "( ");
+			in->cur = strchr(in->cur, '\0');
+		}
+		infix(in, isopr);
+		if (isopr)
+		{
+			RESIZEBUF(in, 2);
+			sprintf(in->cur, " )");
+			in->cur = strchr(in->cur, '\0');
+		}
+	}
+	else
+	{
+		int4	    op = in->curpol->val;
+		INFIX	   nrm;
+
+		in->curpol++;
+		if (op == (int4) '|' && !first)
+		{
+			RESIZEBUF(in, 2);
+			sprintf(in->cur, "( ");
+			in->cur = strchr(in->cur, '\0');
+		}
+
+		nrm.curpol = in->curpol;
+		nrm.op = in->op;
+		nrm.buflen = 16;
+		nrm.cur = nrm.buf = (char *) palloc(sizeof(char) * nrm.buflen);
+
+		/* get right operand */
+		infix(&nrm, false);
+
+		/* get & print left operand */
+		in->curpol = nrm.curpol;
+		infix(in, false);
+
+		/* print operator & right operand */
+		RESIZEBUF(in, 3 + (nrm.cur - nrm.buf));
+		sprintf(in->cur, " %c %s", op, nrm.buf);
+		in->cur = strchr(in->cur, '\0');
+		pfree(nrm.buf);
+
+		if (op == (int4) '|' && !first)
+		{
+			RESIZEBUF(in, 2);
+			sprintf(in->cur, " )");
+			in->cur = strchr(in->cur, '\0');
+		}
+	}
+}
+
+Datum
+ltxtq_out(PG_FUNCTION_ARGS)
+{
+	ltxtquery  *query = PG_GETARG_LTXTQUERY(0);
+	INFIX	   nrm;
+
+	if (query->size == 0)
+		elog(ERROR, "Empty");
+	nrm.curpol = GETQUERY(query);
+	nrm.buflen = 32;
+	nrm.cur = nrm.buf = (char *) palloc(sizeof(char) * nrm.buflen);
+	*(nrm.cur) = '\0';
+	nrm.op = GETOPERAND(query);
+	infix(&nrm, true);
+
+	PG_FREE_IF_COPY(query, 0);
+	PG_RETURN_POINTER(nrm.buf);
+}
+
--- a/contrib/ltree/ltxtquery_op.c
+++ b/contrib/ltree/ltxtquery_op.c
@ -0,0 +1,99 @@
+/*
+ * txtquery operations with ltree 
+ * Teodor Sigaev <teodor@stack.net>
+ */
+
+#include "ltree.h"
+#include <ctype.h>
+
+PG_FUNCTION_INFO_V1(ltxtq_exec);
+PG_FUNCTION_INFO_V1(ltxtq_rexec);
+
+/*
+ * check for boolean condition
+ */
+bool 
+execute(ITEM * curitem, void *checkval, bool calcnot, bool (*chkcond) (void *checkval, ITEM * val)) {
+	if (curitem->type == VAL)
+		return (*chkcond) (checkval, curitem);
+	else if (curitem->val == (int4) '!') {
+		return (calcnot) ?
+			((execute(curitem + 1, checkval, calcnot, chkcond)) ? false : true)
+			: true;
+	} else if (curitem->val == (int4) '&') {
+		if (execute(curitem + curitem->left, checkval, calcnot, chkcond))   
+			return execute(curitem + 1, checkval, calcnot, chkcond);
+		else
+			return false;
+	} else   {						       /* |-operator */
+		if (execute(curitem + curitem->left, checkval, calcnot, chkcond))
+			return true;
+		else
+			return execute(curitem + 1, checkval, calcnot, chkcond);
+	}
+	return false;
+}
+
+typedef struct {
+	ltree	*node;
+	char       *operand;
+} CHKVAL;
+
+static bool
+checkcondition_str(void* checkval, ITEM * val) {
+	ltree_level *level = LTREE_FIRST( ((CHKVAL*)checkval)->node );
+	int tlen = ((CHKVAL*)checkval)->node->numlevel;
+	char *op = ((CHKVAL*)checkval)->operand + val->distance;
+        int (*cmpptr)(const char *,const char *,size_t);
+
+	cmpptr = ( val->flag & LVAR_INCASE ) ? strncasecmp : strncmp;
+	while( tlen > 0 ) {
+		if ( val->flag & LVAR_SUBLEXEM ) {
+			if ( compare_subnode(level, op, val->length, cmpptr, (val->flag & LVAR_ANYEND) ) )
+				return true;
+		} else if ( 
+			(
+				val->length == level->len ||
+				( level->len > val->length && (val->flag & LVAR_ANYEND) )
+			) &&
+				(*cmpptr)( op, level->name, val->length) == 0 )
+			return true;
+
+		tlen--;
+		level = LEVEL_NEXT(level); 
+	}
+
+	return false;
+}
+
+Datum
+ltxtq_exec(PG_FUNCTION_ARGS) {
+	ltree     *val = PG_GETARG_LTREE(0);
+	ltxtquery  *query = PG_GETARG_LTXTQUERY(1);
+	CHKVAL	  chkval;
+	bool	    result;
+
+	chkval.node = val;
+	chkval.operand = GETOPERAND(query);
+
+	result = execute(
+		GETQUERY(query),
+		&chkval,
+		true,
+		checkcondition_str
+	);
+
+	PG_FREE_IF_COPY(val, 0);
+	PG_FREE_IF_COPY(query, 1);
+	PG_RETURN_BOOL(result);
+}
+
+Datum
+ltxtq_rexec(PG_FUNCTION_ARGS) {
+	PG_RETURN_DATUM( DirectFunctionCall2( ltxtq_exec,
+		PG_GETARG_DATUM(1),
+		PG_GETARG_DATUM(0)
+	) );
+}
+
+
--- a/contrib/ltree/patch.72
+++ b/contrib/ltree/patch.72
@ -0,0 +1,71 @@
+*** ltree.sql.in	Tue Jul 23 18:49:12 2002
+--- ltree.sql.in.72	Wed Jul 17 18:59:08 2002
+***************
+*** 177,188 ****
+  
+  
+  -- B-tree support
+! INSERT INTO pg_opclass (opcamid, opcname, opcnamespace, opcowner, opcintype, opcdefault, opckeytype)
+      VALUES (
+          (SELECT oid FROM pg_am WHERE amname = 'btree'),
+          'ltree_ops',
+- 	(SELECT oid FROM pg_namespace WHERE nspname = 'pg_catalog'),
+- 	1,      -- UID of superuser is hardwired to 1 as of PG 7.3
+          (SELECT oid FROM pg_type WHERE typname = 'ltree'),
+          true,
+          0);
+--- 177,186 ----
+  
+  
+  -- B-tree support
+! INSERT INTO pg_opclass (opcamid, opcname, opcintype, opcdefault, opckeytype)
+      VALUES (
+          (SELECT oid FROM pg_am WHERE amname = 'btree'),
+          'ltree_ops',
+          (SELECT oid FROM pg_type WHERE typname = 'ltree'),
+          true,
+          0);
+***************
+*** 376,386 ****
+  create function ltree_union(bytea, opaque) returns int4 as 'MODULE_PATHNAME' language 'C';
+  create function ltree_same(opaque, opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+  
+! INSERT INTO pg_opclass (opcamid, opcname, opcnamespace, opcowner, opcintype, opckeytype, opcdefault)
+!    SELECT pg_am.oid, 'gist_ltree_ops', 
+! 	(SELECT oid FROM pg_namespace WHERE nspname = 'pg_catalog'),
+! 	1,      -- UID of superuser is hardwired to 1 as of PG 7.3
+! 	pg_type.oid, pg_key.oid, true
+     FROM pg_type, pg_am, pg_type pg_key
+     WHERE pg_type.typname = 'ltree' and
+     pg_am.amname='gist' and
+--- 374,381 ----
+  create function ltree_union(bytea, opaque) returns int4 as 'MODULE_PATHNAME' language 'C';
+  create function ltree_same(opaque, opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+  
+! INSERT INTO pg_opclass (opcamid, opcname, opcintype, opckeytype, opcdefault)
+!    SELECT pg_am.oid, 'gist_ltree_ops', pg_type.oid, pg_key.oid, true
+     FROM pg_type, pg_am, pg_type pg_key
+     WHERE pg_type.typname = 'ltree' and
+     pg_am.amname='gist' and
+***************
+*** 720,730 ****
+  create function _ltree_union(bytea, opaque) returns int4 as 'MODULE_PATHNAME' language 'C';
+  create function _ltree_same(opaque, opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+  
+! INSERT INTO pg_opclass (opcamid, opcname, opcnamespace, opcowner, opcintype, opckeytype, opcdefault)
+!    SELECT pg_am.oid, 'gist__ltree_ops', 
+! 	(SELECT oid FROM pg_namespace WHERE nspname = 'pg_catalog'),
+! 	1,      -- UID of superuser is hardwired to 1 as of PG 7.3
+! 	pg_type.oid, pg_key.oid, true
+     FROM pg_type, pg_am, pg_type pg_key
+     WHERE pg_type.typname = '_ltree' and
+     pg_am.amname='gist' and
+--- 715,722 ----
+  create function _ltree_union(bytea, opaque) returns int4 as 'MODULE_PATHNAME' language 'C';
+  create function _ltree_same(opaque, opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
+  
+! INSERT INTO pg_opclass (opcamid, opcname, opcintype, opckeytype, opcdefault)
+!    SELECT pg_am.oid, 'gist__ltree_ops', pg_type.oid, pg_key.oid, true
+     FROM pg_type, pg_am, pg_type pg_key
+     WHERE pg_type.typname = '_ltree' and
+     pg_am.amname='gist' and
--- a/contrib/ltree/sql/ltree.sql
+++ b/contrib/ltree/sql/ltree.sql
@ -0,0 +1,238 @@
+\set ECHO none
+\i ltree.sql
+\set ECHO all
+
+select ''::ltree;
+select '1'::ltree;
+select '1.2'::ltree;
+select '1.2._3'::ltree;
+
+select subltree('Top.Child1.Child2',1,2);
+select subpath('Top.Child1.Child2',1,2);
+select subpath('Top.Child1.Child2',-1,1);
+select subpath('Top.Child1.Child2',0,-2);
+select subpath('Top.Child1.Child2',0,-1);
+select subpath('Top.Child1.Child2',0,0);
+select subpath('Top.Child1.Child2',1,0);
+select subpath('Top.Child1.Child2',0);
+select subpath('Top.Child1.Child2',1);
+
+select 'Top.Child1.Child2'::ltree || 'Child3'::text;
+select 'Top.Child1.Child2'::ltree || 'Child3'::ltree;
+select 'Top_0'::ltree || 'Top.Child1.Child2'::ltree;
+select 'Top.Child1.Child2'::ltree || ''::ltree;
+select ''::ltree || 'Top.Child1.Child2'::ltree;
+
+select '1'::lquery;
+select '4|3|2'::lquery;
+select '1.2'::lquery;
+select '1.4|3|2'::lquery;
+select '1.0'::lquery;
+select '4|3|2.0'::lquery;
+select '1.2.0'::lquery;
+select '1.4|3|2.0'::lquery;
+select '1.*'::lquery;
+select '4|3|2.*'::lquery;
+select '1.2.*'::lquery;
+select '1.4|3|2.*'::lquery;
+select '*.1.*'::lquery;
+select '*.4|3|2.*'::lquery;
+select '*.1.2.*'::lquery;
+select '*.1.4|3|2.*'::lquery;
+select '1.*.4|3|2'::lquery;
+select '1.*.4|3|2.0'::lquery;
+select '1.*.4|3|2.*{1,4}'::lquery;
+select '1.*.4|3|2.*{,4}'::lquery;
+select '1.*.4|3|2.*{1,}'::lquery;
+select '1.*.4|3|2.*{1}'::lquery;
+select 'qwerty%@*.tu'::lquery;
+
+select nlevel('1.2.3.4');
+select '1.2'::ltree  < '2.2'::ltree;
+select '1.2'::ltree  <= '2.2'::ltree;
+select '2.2'::ltree  = '2.2'::ltree;
+select '3.2'::ltree  >= '2.2'::ltree;
+select '3.2'::ltree  > '2.2'::ltree;
+
+select '1.2.3'::ltree @> '1.2.3.4'::ltree;
+select '1.2.3.4'::ltree @> '1.2.3.4'::ltree;
+select '1.2.3.4.5'::ltree @> '1.2.3.4'::ltree;
+select '1.3.3'::ltree @> '1.2.3.4'::ltree;
+
+select 'a.b.c.d.e'::ltree ~ 'a.b.c.d.e';
+select 'a.b.c.d.e'::ltree ~ 'A.b.c.d.e';
+select 'a.b.c.d.e'::ltree ~ 'A@.b.c.d.e';
+select 'aa.b.c.d.e'::ltree ~ 'A@.b.c.d.e';
+select 'aa.b.c.d.e'::ltree ~ 'A*.b.c.d.e';
+select 'aa.b.c.d.e'::ltree ~ 'A*@.b.c.d.e';
+select 'aa.b.c.d.e'::ltree ~ 'A*@|g.b.c.d.e';
+select 'g.b.c.d.e'::ltree ~ 'A*@|g.b.c.d.e';
+select 'a.b.c.d.e'::ltree ~ 'a.b.c.d.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*{3}.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*{2}.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*{4}.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*{,4}.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*{2,}.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*{2,4}.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*{2,3}.e';
+select 'a.b.c.d.e'::ltree ~ 'a.*{2,3}';
+select 'a.b.c.d.e'::ltree ~ 'a.*{2,4}';
+select 'a.b.c.d.e'::ltree ~ 'a.*{2,5}';
+select 'a.b.c.d.e'::ltree ~ '*{2,3}.e';
+select 'a.b.c.d.e'::ltree ~ '*{2,4}.e';
+select 'a.b.c.d.e'::ltree ~ '*{2,5}.e';
+select 'a.b.c.d.e'::ltree ~ '*.e';
+select 'a.b.c.d.e'::ltree ~ '*.e.*';
+select 'a.b.c.d.e'::ltree ~ '*.d.*';
+select 'a.b.c.d.e'::ltree ~ '*.a.*.d.*';
+select 'a.b.c.d.e'::ltree ~ '*.!d.*';
+select 'a.b.c.d.e'::ltree ~ '*.!d';
+select 'a.b.c.d.e'::ltree ~ '!d.*';
+select 'a.b.c.d.e'::ltree ~ '!a.*';
+select 'a.b.c.d.e'::ltree ~ '*.!e';
+select 'a.b.c.d.e'::ltree ~ '*.!e.*';
+select 'a.b.c.d.e'::ltree ~ 'a.*.!e';
+select 'a.b.c.d.e'::ltree ~ 'a.*.!d';
+select 'a.b.c.d.e'::ltree ~ 'a.*.!d.*';
+select 'a.b.c.d.e'::ltree ~ 'a.*.!f.*';
+select 'a.b.c.d.e'::ltree ~ '*.a.*.!f.*';
+select 'a.b.c.d.e'::ltree ~ '*.a.*.!d.*';
+select 'a.b.c.d.e'::ltree ~ '*.a.!d.*';
+select 'a.b.c.d.e'::ltree ~ '*.a.!d';
+select 'a.b.c.d.e'::ltree ~ 'a.!d.*';
+select 'a.b.c.d.e'::ltree ~ '*.a.*.!d.*';
+select 'a.b.c.d.e'::ltree ~ '*.!b.*';
+select 'a.b.c.d.e'::ltree ~ '*.!b.c.*';
+select 'a.b.c.d.e'::ltree ~ '*.!b.*.c.*';
+select 'a.b.c.d.e'::ltree ~ '!b.*.c.*';
+select 'a.b.c.d.e'::ltree ~ '!b.b.*';
+select 'a.b.c.d.e'::ltree ~ '!b.*.e';
+select 'a.b.c.d.e'::ltree ~ '!b.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ '!b.*.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ '*{2}.!b.*.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ '*{1}.!b.*.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ '*{1}.!b.*{1}.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ 'a.!b.*{1}.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ '!b.*{1}.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ '*.!b.*{1}.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ '*.!b.*.!c.*.e';
+select 'a.b.c.d.e'::ltree ~ '!b.!c.*';
+select 'a.b.c.d.e'::ltree ~ '!b.*.!c.*';
+select 'a.b.c.d.e'::ltree ~ '*{2}.!b.*.!c.*';
+select 'a.b.c.d.e'::ltree ~ '*{1}.!b.*.!c.*';
+select 'a.b.c.d.e'::ltree ~ '*{1}.!b.*{1}.!c.*';
+select 'a.b.c.d.e'::ltree ~ 'a.!b.*{1}.!c.*';
+select 'a.b.c.d.e'::ltree ~ '!b.*{1}.!c.*';
+select 'a.b.c.d.e'::ltree ~ '*.!b.*{1}.!c.*';
+select 'a.b.c.d.e'::ltree ~ '*.!b.*.!c.*';
+
+select 'QWER_TY'::ltree ~ 'q%@*';
+select 'QWER_TY'::ltree ~ 'Q_t%@*';
+select 'QWER_GY'::ltree ~ 'q_t%@*';
+
+--ltxtquery
+select '!tree & aWdf@*'::ltxtquery;
+select 'tree & aw_qw%*'::ltxtquery;
+select 'ltree.awdfg'::ltree @ '!tree & aWdf@*'::ltxtquery;
+select 'tree.awdfg'::ltree @ '!tree & aWdf@*'::ltxtquery;
+select 'tree.awdfg'::ltree @ '!tree | aWdf@*'::ltxtquery;
+select 'tree.awdfg'::ltree @ 'tree | aWdf@*'::ltxtquery;
+select 'tree.awdfg'::ltree @ 'tree & aWdf@*'::ltxtquery;
+select 'tree.awdfg'::ltree @ 'tree & aWdf@'::ltxtquery;
+select 'tree.awdfg'::ltree @ 'tree & aWdf*'::ltxtquery;
+select 'tree.awdfg'::ltree @ 'tree & aWdf'::ltxtquery;
+select 'tree.awdfg'::ltree @ 'tree & awdf*'::ltxtquery;
+select 'tree.awdfg'::ltree @ 'tree & aWdfg@'::ltxtquery;
+select 'tree.awdfg_qwerty'::ltree @ 'tree & aw_qw%*'::ltxtquery;
+select 'tree.awdfg_qwerty'::ltree @ 'tree & aw_rw%*'::ltxtquery;
+
+--arrays
+
+select '{1.2.3}'::ltree[] @> '1.2.3.4';
+select '{1.2.3.4}'::ltree[] @> '1.2.3.4';
+select '{1.2.3.4.5}'::ltree[] @> '1.2.3.4';
+select '{1.3.3}'::ltree[] @> '1.2.3.4';
+select '{5.67.8, 1.2.3}'::ltree[] @> '1.2.3.4';
+select '{5.67.8, 1.2.3.4}'::ltree[] @> '1.2.3.4';
+select '{5.67.8, 1.2.3.4.5}'::ltree[] @> '1.2.3.4';
+select '{5.67.8, 1.3.3}'::ltree[] @> '1.2.3.4';
+select '{1.2.3, 7.12.asd}'::ltree[] @> '1.2.3.4';
+select '{1.2.3.4, 7.12.asd}'::ltree[] @> '1.2.3.4';
+select '{1.2.3.4.5, 7.12.asd}'::ltree[] @> '1.2.3.4';
+select '{1.3.3, 7.12.asd}'::ltree[] @> '1.2.3.4';
+select '{ltree.asd, tree.awdfg}'::ltree[] @ 'tree & aWdfg@'::ltxtquery;
+select '{j.k.l.m, g.b.c.d.e}'::ltree[] ~ 'A*@|g.b.c.d.e';
+
+--exractors
+select ('{3456,1.2.3.34}'::ltree[] ?@> '1.2.3.4') is null;
+select '{3456,1.2.3}'::ltree[] ?@> '1.2.3.4';
+select '{3456,1.2.3.4}'::ltree[] ?<@ '1.2.3';
+select ('{3456,1.2.3.4}'::ltree[] ?<@ '1.2.5') is null;
+select '{ltree.asd, tree.awdfg}'::ltree[] ?@ 'tree & aWdfg@'::ltxtquery;
+select '{j.k.l.m, g.b.c.d.e}'::ltree[] ?~ 'A*@|g.b.c.d.e';
+
+create table ltreetest (t ltree);
+\copy ltreetest from 'data/ltree.data'
+
+select * from ltreetest where t <  '12.3' order by t asc;
+select * from ltreetest where t <= '12.3' order by t asc;
+select * from ltreetest where t =  '12.3' order by t asc;
+select * from ltreetest where t >= '12.3' order by t asc;
+select * from ltreetest where t >  '12.3' order by t asc;
+select * from ltreetest where t @> '1.1.1' order by t asc;
+select * from ltreetest where t <@ '1.1.1' order by t asc;
+select * from ltreetest where t ~ '1.1.1.*' order by t asc;
+select * from ltreetest where t ~ '*.1' order by t asc;
+select * from ltreetest where t ~ '23.*.1' order by t asc;
+select * from ltreetest where t ~ '23.*{1}.1' order by t asc;
+select * from ltreetest where t @ '23 & 1' order by t asc;
+
+create unique index tstidx on ltreetest (t);
+set enable_seqscan=off;
+
+select * from ltreetest where t <  '12.3' order by t asc;
+select * from ltreetest where t <= '12.3' order by t asc;
+select * from ltreetest where t =  '12.3' order by t asc;
+select * from ltreetest where t >= '12.3' order by t asc;
+select * from ltreetest where t >  '12.3' order by t asc;
+
+drop index tstidx;
+create index tstidx on ltreetest using gist (t);
+set enable_seqscan=off;
+
+select * from ltreetest where t <  '12.3' order by t asc;
+select * from ltreetest where t <= '12.3' order by t asc;
+select * from ltreetest where t =  '12.3' order by t asc;
+select * from ltreetest where t >= '12.3' order by t asc;
+select * from ltreetest where t >  '12.3' order by t asc;
+select * from ltreetest where t @> '1.1.1' order by t asc;
+select * from ltreetest where t <@ '1.1.1' order by t asc;
+select * from ltreetest where t ~ '1.1.1.*' order by t asc;
+select * from ltreetest where t ~ '*.1' order by t asc;
+select * from ltreetest where t ~ '23.*.1' order by t asc;
+select * from ltreetest where t ~ '23.*{1}.1' order by t asc;
+select * from ltreetest where t @ '23 & 1' order by t asc;
+
+create table _ltreetest (t ltree[]);
+\copy _ltreetest from 'data/_ltree.data'
+
+select count(*) from _ltreetest where t @> '1.1.1' ;
+select count(*) from _ltreetest where t <@ '1.1.1' ;
+select count(*) from _ltreetest where t ~ '1.1.1.*' ;
+select count(*) from _ltreetest where t ~ '*.1' ;
+select count(*) from _ltreetest where t ~ '23.*.1' ;
+select count(*) from _ltreetest where t ~ '23.*{1}.1' ;
+select count(*) from _ltreetest where t @ '23 & 1' ;
+
+create index _tstidx on _ltreetest using gist (t);
+set enable_seqscan=off;
+
+select count(*) from _ltreetest where t @> '1.1.1' ;
+select count(*) from _ltreetest where t <@ '1.1.1' ;
+select count(*) from _ltreetest where t ~ '1.1.1.*' ;
+select count(*) from _ltreetest where t ~ '*.1' ;
+select count(*) from _ltreetest where t ~ '23.*.1' ;
+select count(*) from _ltreetest where t ~ '23.*{1}.1' ;
+select count(*) from _ltreetest where t @ '23 & 1' ;
+