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Remove the Query structure from the executor's API. This allows us to stop

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storing mostly-redundant Query trees in prepared statements, portals, etc.
To replace Query, a new node type called PlannedStmt is inserted by the
planner at the top of a completed plan tree; this carries just the fields of
Query that are still needed at runtime.  The statement lists kept in portals
etc. now consist of intermixed PlannedStmt and bare utility-statement nodes
--- no Query.  This incidentally allows us to remove some fields from Query
and Plan nodes that shouldn't have been there in the first place.

Still to do: simplify the execution-time range table; at the moment the
range table passed to the executor still contains Query trees for subqueries.

initdb forced due to change of stored rules.
This commit is contained in:
Tom Lane
2007-02-20 17:32:18 +00:00
parent 71b0cf2f6b
commit 9cbd0c155d
39 changed files with 1172 additions and 897 deletions
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53
src/backend/utils/mmgr/portalmem.c
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@@ -12,7 +12,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/mmgr/portalmem.c,v 1.98 2007/01/05 22:19:47 momjian Exp $
* $PostgreSQL: pgsql/src/backend/utils/mmgr/portalmem.c,v 1.99 2007/02/20 17:32:17 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -141,29 +141,45 @@ GetPortalByName(const char *name)
}
/*
* PortalListGetPrimaryQuery
* Get the "primary" Query within a portal, ie, the one marked canSetTag.
* PortalListGetPrimaryStmt
* Get the "primary" stmt within a portal, ie, the one marked canSetTag.
*
* Returns NULL if no such Query. If multiple Query structs within the
* Returns NULL if no such stmt. If multiple PlannedStmt structs within the
* portal are marked canSetTag, returns the first one. Neither of these
* cases should occur in present usages of this function.
*
* Copes if given a list of Querys --- can't happen in a portal, but this
* code also supports prepared statements, which need both cases.
*
* Note: the reason this is just handed a List is so that prepared statements
* can share the code. For use with a portal, use PortalGetPrimaryQuery
* can share the code. For use with a portal, use PortalGetPrimaryStmt
* rather than calling this directly.
*/
Query *
PortalListGetPrimaryQuery(List *parseTrees)
Node *
PortalListGetPrimaryStmt(List *stmts)
{
ListCell *lc;
foreach(lc, parseTrees)
foreach(lc, stmts)
{
Query *query = (Query *) lfirst(lc);
Node *stmt = (Node *) lfirst(lc);
Assert(IsA(query, Query));
if (query->canSetTag)
return query;
if (IsA(stmt, PlannedStmt))
{
if (((PlannedStmt *) stmt)->canSetTag)
return stmt;
}
else if (IsA(stmt, Query))
{
if (((Query *) stmt)->canSetTag)
return stmt;
}
else
{
/* Utility stmts are assumed canSetTag if they're the only stmt */
if (list_length(stmts) == 1)
return stmt;
}
}
return NULL;
}
@@ -261,30 +277,25 @@ CreateNewPortal(void)
* (before rewriting) was an empty string. Also, the passed commandTag must
* be a pointer to a constant string, since it is not copied. The caller is
* responsible for ensuring that the passed prepStmtName (if any), sourceText
* (if any), parse and plan trees have adequate lifetime. Also, queryContext
* must accurately describe the location of the parse trees.
* (if any), and plan trees have adequate lifetime.
*/
void
PortalDefineQuery(Portal portal,
const char *prepStmtName,
const char *sourceText,
const char *commandTag,
List *parseTrees,
List *planTrees,
List *stmts,
MemoryContext queryContext)
{
AssertArg(PortalIsValid(portal));
AssertState(portal->queryContext == NULL); /* else defined already */
Assert(list_length(parseTrees) == list_length(planTrees));
Assert(commandTag != NULL || parseTrees == NIL);
Assert(commandTag != NULL || stmts == NIL);
portal->prepStmtName = prepStmtName;
portal->sourceText = sourceText;
portal->commandTag = commandTag;
portal->parseTrees = parseTrees;
portal->planTrees = planTrees;
portal->stmts = stmts;
portal->queryContext = queryContext;
}