@ -16,6 +16,7 @@
# include "access/genam.h"
# include "access/heapam.h"
# include "access/heapam_xlog.h"
# include "access/multixact.h"
# include "access/reloptions.h"
# include "access/relscan.h"
@ -1322,11 +1323,7 @@ ExecuteTruncate(TruncateStmt *stmt)
{
List * rels = NIL ;
List * relids = NIL ;
List * seq_relids = NIL ;
EState * estate ;
ResultRelInfo * resultRelInfos ;
ResultRelInfo * resultRelInfo ;
SubTransactionId mySubid ;
List * relids_logged = NIL ;
ListCell * cell ;
/*
@ -1350,6 +1347,9 @@ ExecuteTruncate(TruncateStmt *stmt)
truncate_check_rel ( rel ) ;
rels = lappend ( rels , rel ) ;
relids = lappend_oid ( relids , myrelid ) ;
/* Log this relation only if needed for logical decoding */
if ( RelationIsLogicallyLogged ( rel ) )
relids_logged = lappend_oid ( relids_logged , myrelid ) ;
if ( recurse )
{
@ -1370,6 +1370,9 @@ ExecuteTruncate(TruncateStmt *stmt)
truncate_check_rel ( rel ) ;
rels = lappend ( rels , rel ) ;
relids = lappend_oid ( relids , childrelid ) ;
/* Log this relation only if needed for logical decoding */
if ( RelationIsLogicallyLogged ( rel ) )
relids_logged = lappend_oid ( relids_logged , childrelid ) ;
}
}
else if ( rel - > rd_rel - > relkind = = RELKIND_PARTITIONED_TABLE )
@ -1379,7 +1382,47 @@ ExecuteTruncate(TruncateStmt *stmt)
errhint ( " Do not specify the ONLY keyword, or use TRUNCATE ONLY on the partitions directly. " ) ) ) ;
}
ExecuteTruncateGuts ( rels , relids , relids_logged ,
stmt - > behavior , stmt - > restart_seqs ) ;
/* And close the rels */
foreach ( cell , rels )
{
Relation rel = ( Relation ) lfirst ( cell ) ;
heap_close ( rel , NoLock ) ;
}
}
/*
* ExecuteTruncateGuts
*
* Internal implementation of TRUNCATE . This is called by the actual TRUNCATE
* command ( see above ) as well as replication subscribers that execute a
* replicated TRUNCATE action .
*
* explicit_rels is the list of Relations to truncate that the command
* specified . relids is the list of Oids corresponding to explicit_rels .
* relids_logged is the list of Oids ( a subset of relids ) that require
* WAL - logging . This is all a bit redundant , but the existing callers have
* this information handy in this form .
*/
void
ExecuteTruncateGuts ( List * explicit_rels , List * relids , List * relids_logged ,
DropBehavior behavior , bool restart_seqs )
{
List * rels ;
List * seq_relids = NIL ;
EState * estate ;
ResultRelInfo * resultRelInfos ;
ResultRelInfo * resultRelInfo ;
SubTransactionId mySubid ;
ListCell * cell ;
Oid * logrelids ;
/*
* Open , exclusive - lock , and check all the explicitly - specified relations
*
* In CASCADE mode , suck in all referencing relations as well . This
* requires multiple iterations to find indirectly - dependent relations . At
* each phase , we need to exclusive - lock new rels before looking for their
@ -1387,7 +1430,8 @@ ExecuteTruncate(TruncateStmt *stmt)
* soon as we open it , to avoid a faux pas such as holding lock for a long
* time on a rel we have no permissions for .
*/
if ( stmt - > behavior = = DROP_CASCADE )
rels = list_copy ( explicit_rels ) ;
if ( behavior = = DROP_CASCADE )
{
for ( ; ; )
{
@ -1409,6 +1453,9 @@ ExecuteTruncate(TruncateStmt *stmt)
truncate_check_rel ( rel ) ;
rels = lappend ( rels , rel ) ;
relids = lappend_oid ( relids , relid ) ;
/* Log this relation only if needed for logical decoding */
if ( RelationIsLogicallyLogged ( rel ) )
relids_logged = lappend_oid ( relids_logged , relid ) ;
}
}
}
@ -1421,7 +1468,7 @@ ExecuteTruncate(TruncateStmt *stmt)
# ifdef USE_ASSERT_CHECKING
heap_truncate_check_FKs ( rels , false ) ;
# else
if ( stmt - > behavior = = DROP_RESTRICT )
if ( behavior = = DROP_RESTRICT )
heap_truncate_check_FKs ( rels , false ) ;
# endif
@ -1431,7 +1478,7 @@ ExecuteTruncate(TruncateStmt *stmt)
* We want to do this early since it ' s pointless to do all the truncation
* work only to fail on sequence permissions .
*/
if ( stmt - > restart_seqs )
if ( restart_seqs )
{
foreach ( cell , rels )
{
@ -1586,6 +1633,41 @@ ExecuteTruncate(TruncateStmt *stmt)
ResetSequence ( seq_relid ) ;
}
/*
* Write a WAL record to allow this set of actions to be logically decoded .
*
* Assemble an array of relids so we can write a single WAL record for the
* whole action .
*/
if ( list_length ( relids_logged ) > 0 )
{
xl_heap_truncate xlrec ;
int i = 0 ;
/* should only get here if wal_level >= logical */
Assert ( XLogLogicalInfoActive ( ) ) ;
logrelids = palloc ( list_length ( relids_logged ) * sizeof ( Oid ) ) ;
foreach ( cell , relids_logged )
logrelids [ i + + ] = lfirst_oid ( cell ) ;
xlrec . dbId = MyDatabaseId ;
xlrec . nrelids = list_length ( relids_logged ) ;
xlrec . flags = 0 ;
if ( behavior = = DROP_CASCADE )
xlrec . flags | = XLH_TRUNCATE_CASCADE ;
if ( restart_seqs )
xlrec . flags | = XLH_TRUNCATE_RESTART_SEQS ;
XLogBeginInsert ( ) ;
XLogRegisterData ( ( char * ) & xlrec , SizeOfHeapTruncate ) ;
XLogRegisterData ( ( char * ) logrelids , list_length ( relids_logged ) * sizeof ( Oid ) ) ;
XLogSetRecordFlags ( XLOG_INCLUDE_ORIGIN ) ;
( void ) XLogInsert ( RM_HEAP_ID , XLOG_HEAP_TRUNCATE ) ;
}
/*
* Process all AFTER STATEMENT TRUNCATE triggers .
*/
@ -1603,7 +1685,11 @@ ExecuteTruncate(TruncateStmt *stmt)
/* We can clean up the EState now */
FreeExecutorState ( estate ) ;
/* And close the rels (can't do this while EState still holds refs) */
/*
* Close any rels opened by CASCADE ( can ' t do this while EState still
* holds refs )
*/
rels = list_difference_ptr ( rels , explicit_rels ) ;
foreach ( cell , rels )
{
Relation rel = ( Relation ) lfirst ( cell ) ;
Peter Eisentraut
7 years ago