@ -14,13 +14,14 @@
*
*
* IDENTIFICATION
* $ PostgreSQL : pgsql / src / backend / optimizer / prep / prepunion . c , v 1.112 2004 / 05 / 30 23 : 40 : 29 neilc Exp $
* $ PostgreSQL : pgsql / src / backend / optimizer / prep / prepunion . c , v 1.113 2004 / 06 / 05 01 : 55 : 04 tgl Exp $
*
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
# include "postgres.h"
# include "access/heapam.h"
# include "catalog/pg_type.h"
# include "nodes/makefuncs.h"
# include "optimizer/clauses.h"
@ -39,8 +40,10 @@ typedef struct
{
Index old_rt_index ;
Index new_rt_index ;
Oid old_relid ;
Oid new_relid ;
TupleDesc old_tupdesc ;
TupleDesc new_tupdesc ;
char * old_rel_name ;
char * new_rel_name ;
} adjust_inherited_attrs_context ;
static Plan * recurse_set_operations ( Node * setOp , Query * parse ,
@ -65,7 +68,8 @@ static bool tlist_same_datatypes(List *tlist, List *colTypes, bool junkOK);
static Node * adjust_inherited_attrs_mutator ( Node * node ,
adjust_inherited_attrs_context * context ) ;
static Relids adjust_relid_set ( Relids relids , Index oldrelid , Index newrelid ) ;
static List * adjust_inherited_tlist ( List * tlist , Oid old_relid , Oid new_relid ) ;
static List * adjust_inherited_tlist ( List * tlist ,
adjust_inherited_attrs_context * context ) ;
/*
@ -787,17 +791,17 @@ expand_inherited_rtentry(Query *parse, Index rti, bool dup_parent)
* We also adjust varattno to match the new table by column name , rather
* than column number . This hack makes it possible for child tables to have
* different column positions for the " same " attribute as a parent , which
* helps ALTER TABLE ADD COLUMN . Unfortunately this isn ' t nearly enough to
* make it work transparently ; there are other places where things fall down
* if children and parents don ' t have the same column numbers for inherited
* attributes . It ' d be better to rip this code out and fix ALTER TABLE . . .
* is necessary for ALTER TABLE ADD COLUMN .
*/
Node *
adjust_inherited_attrs ( Node * node ,
Index old_rt_index , Oid old_relid ,
Index new_rt_index , Oid new_relid )
{
Node * result ;
adjust_inherited_attrs_context context ;
Relation oldrelation ;
Relation newrelation ;
/* Handle simple case simply... */
if ( old_rt_index = = new_rt_index )
@ -806,10 +810,19 @@ adjust_inherited_attrs(Node *node,
return copyObject ( node ) ;
}
/*
* We assume that by now the planner has acquired at least AccessShareLock
* on both rels , and so we need no additional lock now .
*/
oldrelation = heap_open ( old_relid , NoLock ) ;
newrelation = heap_open ( new_relid , NoLock ) ;
context . old_rt_index = old_rt_index ;
context . new_rt_index = new_rt_index ;
context . old_relid = old_relid ;
context . new_relid = new_relid ;
context . old_tupdesc = RelationGetDescr ( oldrelation ) ;
context . new_tupdesc = RelationGetDescr ( newrelation ) ;
context . old_rel_name = RelationGetRelationName ( oldrelation ) ;
context . new_rel_name = RelationGetRelationName ( newrelation ) ;
/*
* Must be prepared to start with a Query or a bare expression tree .
@ -829,13 +842,109 @@ adjust_inherited_attrs(Node *node,
if ( newnode - > commandType = = CMD_UPDATE )
newnode - > targetList =
adjust_inherited_tlist ( newnode - > targetList ,
old_relid ,
new_relid ) ;
& context ) ;
}
return ( Node * ) newnode ;
result = ( Node * ) newnode ;
}
else
result = adjust_inherited_attrs_mutator ( node , & context ) ;
heap_close ( oldrelation , NoLock ) ;
heap_close ( newrelation , NoLock ) ;
return result ;
}
/*
* Translate parent ' s attribute number into child ' s .
*
* For paranoia ' s sake , we match type as well as attribute name .
*/
static AttrNumber
translate_inherited_attnum ( AttrNumber old_attno ,
adjust_inherited_attrs_context * context )
{
Form_pg_attribute att ;
char * attname ;
Oid atttypid ;
int32 atttypmod ;
int newnatts ;
int i ;
if ( old_attno < = 0 | | old_attno > context - > old_tupdesc - > natts )
elog ( ERROR , " attribute %d of relation \" %s \" does not exist " ,
( int ) old_attno , context - > old_rel_name ) ;
att = context - > old_tupdesc - > attrs [ old_attno - 1 ] ;
if ( att - > attisdropped )
elog ( ERROR , " attribute %d of relation \" %s \" does not exist " ,
( int ) old_attno , context - > old_rel_name ) ;
attname = NameStr ( att - > attname ) ;
atttypid = att - > atttypid ;
atttypmod = att - > atttypmod ;
newnatts = context - > new_tupdesc - > natts ;
for ( i = 0 ; i < newnatts ; i + + )
{
att = context - > new_tupdesc - > attrs [ i ] ;
if ( att - > attisdropped )
continue ;
if ( strcmp ( attname , NameStr ( att - > attname ) ) = = 0 )
{
/* Found it, check type */
if ( atttypid ! = att - > atttypid | | atttypmod ! = att - > atttypmod )
elog ( ERROR , " attribute \" %s \" of relation \" %s \" does not match parent's type " ,
attname , context - > new_rel_name ) ;
return ( AttrNumber ) ( i + 1 ) ;
}
}
elog ( ERROR , " attribute \" %s \" of relation \" %s \" does not exist " ,
attname , context - > new_rel_name ) ;
return 0 ; /* keep compiler quiet */
}
/*
* Translate a whole - row Var to be correct for a child table .
*
* In general the child will not have a suitable field layout to be used
* directly , so we translate the simple whole - row Var into a ROW ( ) construct .
*/
static Node *
generate_whole_row ( Var * var ,
adjust_inherited_attrs_context * context )
{
RowExpr * rowexpr ;
List * fields = NIL ;
int oldnatts = context - > old_tupdesc - > natts ;
int i ;
for ( i = 0 ; i < oldnatts ; i + + )
{
Form_pg_attribute att = context - > old_tupdesc - > attrs [ i ] ;
Var * newvar ;
if ( att - > attisdropped )
{
/*
* can ' t use atttypid here , but it doesn ' t really matter
* what type the Const claims to be .
*/
newvar = ( Var * ) makeNullConst ( INT4OID ) ;
}
else
return adjust_inherited_attrs_mutator ( node , & context ) ;
newvar = makeVar ( context - > new_rt_index ,
translate_inherited_attnum ( i + 1 , context ) ,
att - > atttypid ,
att - > atttypmod ,
0 ) ;
fields = lappend ( fields , newvar ) ;
}
rowexpr = makeNode ( RowExpr ) ;
rowexpr - > args = fields ;
rowexpr - > row_typeid = var - > vartype ; /* report parent's rowtype */
rowexpr - > row_format = COERCE_IMPLICIT_CAST ;
return ( Node * ) rowexpr ;
}
static Node *
@ -855,17 +964,16 @@ adjust_inherited_attrs_mutator(Node *node,
var - > varnoold = context - > new_rt_index ;
if ( var - > varattno > 0 )
{
char * attname ;
attname = get_relid_attribute_name ( context - > old_relid ,
var - > varattno ) ;
var - > varattno = get_attnum ( context - > new_relid , attname ) ;
if ( var - > varattno = = InvalidAttrNumber )
elog ( ERROR , " attribute \" %s \" of relation \" %s \" does not exist " ,
attname , get_rel_name ( context - > new_relid ) ) ;
var - > varattno = translate_inherited_attnum ( var - > varattno ,
context ) ;
var - > varoattno = var - > varattno ;
pfree ( attname ) ;
}
else if ( var - > varattno = = 0 )
{
/* expand whole-row reference into a ROW() construct */
return generate_whole_row ( var , context ) ;
}
/* system attributes don't need any translation */
}
return ( Node * ) var ;
}
@ -1022,7 +1130,8 @@ adjust_relid_set(Relids relids, Index oldrelid, Index newrelid)
* Note that this is not needed for INSERT because INSERT isn ' t inheritable .
*/
static List *
adjust_inherited_tlist ( List * tlist , Oid old_relid , Oid new_relid )
adjust_inherited_tlist ( List * tlist ,
adjust_inherited_attrs_context * context )
{
bool changed_it = false ;
ListCell * tl ;
@ -1035,26 +1144,19 @@ adjust_inherited_tlist(List *tlist, Oid old_relid, Oid new_relid)
{
TargetEntry * tle = ( TargetEntry * ) lfirst ( tl ) ;
Resdom * resdom = tle - > resdom ;
char * attname ;
if ( resdom - > resjunk )
continue ; /* ignore junk items */
attname = get_relid_attribute_name ( old_relid , resdom - > resno ) ;
attrno = get_attnum ( new_relid , attname ) ;
if ( attrno = = InvalidAttrNumber )
elog ( ERROR , " attribute \" %s \" of relation \" %s \" does not exist " ,
attname , get_rel_name ( new_relid ) ) ;
attrno = translate_inherited_attnum ( resdom - > resno , context ) ;
if ( resdom - > resno ! = attrno )
{
resdom = ( Resdom * ) copyObject ( ( Node * ) resdom ) ;
resdom - > resno = attrno ;
resdom - > resname = attname ;
tle - > resdom = resdom ;
changed_it = true ;
}
else
pfree ( attname ) ;
}
/*
Tom Lane
21 years ago