diff options
Diffstat (limited to 'src/backend/commands')
| -rw-r--r-- | src/backend/commands/Makefile | 4 | ||||
| -rw-r--r-- | src/backend/commands/discard.c | 71 |
2 files changed, 73 insertions, 2 deletions
diff --git a/src/backend/commands/Makefile b/src/backend/commands/Makefile index f2e5bf52f20..4b25ae6489e 100644 --- a/src/backend/commands/Makefile +++ b/src/backend/commands/Makefile @@ -4,7 +4,7 @@ # Makefile for backend/commands # # IDENTIFICATION -# $PostgreSQL: pgsql/src/backend/commands/Makefile,v 1.35 2007/01/20 17:16:11 petere Exp $ +# $PostgreSQL: pgsql/src/backend/commands/Makefile,v 1.36 2007/04/26 16:13:09 neilc Exp $ # #------------------------------------------------------------------------- @@ -14,7 +14,7 @@ include $(top_builddir)/src/Makefile.global OBJS = aggregatecmds.o alter.o analyze.o async.o cluster.o comment.o \ conversioncmds.o copy.o \ - dbcommands.o define.o explain.o functioncmds.o \ + dbcommands.o define.o discard.o explain.o functioncmds.o \ indexcmds.o lockcmds.o operatorcmds.o opclasscmds.o \ portalcmds.o prepare.o proclang.o \ schemacmds.o sequence.o tablecmds.o tablespace.o trigger.o \ diff --git a/src/backend/commands/discard.c b/src/backend/commands/discard.c new file mode 100644 index 00000000000..d2ae6defd04 --- /dev/null +++ b/src/backend/commands/discard.c @@ -0,0 +1,71 @@ +/*------------------------------------------------------------------------- + * + * discard.c + * The implementation of the DISCARD command + * + * Copyright (c) 1996-2007, PostgreSQL Global Development Group + * + * + * IDENTIFICATION + * $PostgreSQL: pgsql/src/backend/commands/discard.c,v 1.1 2007/04/26 16:13:10 neilc Exp $ + * + *------------------------------------------------------------------------- + */ +#include "postgres.h" + +#include "access/xact.h" +#include "catalog/namespace.h" +#include "commands/async.h" +#include "commands/discard.h" +#include "commands/prepare.h" +#include "commands/variable.h" +#include "utils/plancache.h" +#include "utils/portal.h" + +static void DiscardAll(bool isTopLevel); + +/* + * DISCARD { ALL | TEMP | PLANS } + */ +void +DiscardCommand(DiscardStmt *stmt, bool isTopLevel) +{ + switch (stmt->target) + { + case DISCARD_ALL: + DiscardAll(isTopLevel); + break; + + case DISCARD_PLANS: + ResetPlanCache(); + break; + + case DISCARD_TEMP: + ResetTempTableNamespace(); + break; + + default: + elog(ERROR, "unrecognized DISCARD target: %d", stmt->target); + } +} + +static void +DiscardAll(bool isTopLevel) +{ + /* + * Disallow DISCARD ALL in a transaction block. This is arguably + * inconsistent (we don't make a similar check in the command + * sequence that DISCARD ALL is equivalent to), but the idea is + * to catch mistakes: DISCARD ALL inside a transaction block + * would leave the transaction still uncommitted. + */ + PreventTransactionChain(isTopLevel, "DISCARD ALL"); + + SetPGVariable("session_authorization", NIL, false); + ResetAllOptions(); + DropAllPreparedStatements(); + PortalHashTableDeleteAll(); + Async_UnlistenAll(); + ResetPlanCache(); + ResetTempTableNamespace(); +} |