First phase of plan-invalidation project: create a plan cache management

module and teach PREPARE and protocol-level prepared statements to use it.
In service of this, rearrange utility-statement processing so that parse
analysis does not assume table schemas can't change before execution for
utility statements (necessary because we don't attempt to re-acquire locks
for utility statements when reusing a stored plan).  This requires some
refactoring of the ProcessUtility API, but it ends up cleaner anyway,
for instance we can get rid of the QueryContext global.

Still to do: fix up SPI and related code to use the plan cache; I'm tempted to
try to make SQL functions use it too.  Also, there are at least some aspects
of system state that we want to ensure remain the same during a replan as in
the original processing; search_path certainly ought to behave that way for
instance, and perhaps there are others.

1 files changed, 2 insertions, 9 deletions

diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 87384df8a2d..b2918558305 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/postmaster/autovacuum.c,v 1.33 2007/03/07 13:35:02 alvherre Exp $
+ *	  $PostgreSQL: pgsql/src/backend/postmaster/autovacuum.c,v 1.34 2007/03/13 00:33:41 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1248,13 +1248,6 @@ autovacuum_do_vac_analyze(Oid relid, bool dovacuum, bool doanalyze,
 
 	vacstmt = makeNode(VacuumStmt);
 
-	/*
-	 * Point QueryContext to the autovac memory context to fake out the
-	 * PreventTransactionChain check inside vacuum().  Note that this is also
-	 * why we palloc vacstmt instead of just using a local variable.
-	 */
-	QueryContext = CurrentMemoryContext;
-
 	/* Set up command parameters */
 	vacstmt->vacuum = dovacuum;
 	vacstmt->full = false;
@@ -1267,7 +1260,7 @@ autovacuum_do_vac_analyze(Oid relid, bool dovacuum, bool doanalyze,
 	/* Let pgstat know what we're doing */
 	autovac_report_activity(vacstmt, relid);
 
-	vacuum(vacstmt, list_make1_oid(relid));
+	vacuum(vacstmt, list_make1_oid(relid), true);
 
 	pfree(vacstmt);
 	MemoryContextSwitchTo(old_cxt);