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-rw-r--r--src/backend/optimizer/prep/preptlist.c237
1 files changed, 0 insertions, 237 deletions
diff --git a/src/backend/optimizer/prep/preptlist.c b/src/backend/optimizer/prep/preptlist.c
deleted file mode 100644
index 1cc9f5af489..00000000000
--- a/src/backend/optimizer/prep/preptlist.c
+++ /dev/null
@@ -1,237 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * preptlist.c
- * Routines to preprocess the parse tree target list
- *
- * This module takes care of altering the query targetlist as needed for
- * INSERT, UPDATE, and DELETE queries. For INSERT and UPDATE queries,
- * the targetlist must contain an entry for each attribute of the target
- * relation in the correct order. For both UPDATE and DELETE queries,
- * we need a junk targetlist entry holding the CTID attribute --- the
- * executor relies on this to find the tuple to be replaced/deleted.
- *
- *
- * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- * IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/prep/preptlist.c,v 1.53 2002/06/20 20:29:31 momjian Exp $
- *
- *-------------------------------------------------------------------------
- */
-
-#include "postgres.h"
-
-#include "access/heapam.h"
-#include "catalog/pg_type.h"
-#include "nodes/makefuncs.h"
-#include "optimizer/prep.h"
-#include "parser/parsetree.h"
-
-
-static List *expand_targetlist(List *tlist, int command_type,
- Index result_relation, List *range_table);
-
-
-/*
- * preprocess_targetlist
- * Driver for preprocessing the parse tree targetlist.
- *
- * Returns the new targetlist.
- */
-List *
-preprocess_targetlist(List *tlist,
- int command_type,
- Index result_relation,
- List *range_table)
-{
- /*
- * Sanity check: if there is a result relation, it'd better be a real
- * relation not a subquery. Else parser or rewriter messed up.
- */
- if (result_relation)
- {
- RangeTblEntry *rte = rt_fetch(result_relation, range_table);
-
- if (rte->subquery != NULL || rte->relid == InvalidOid)
- elog(ERROR, "preprocess_targetlist: subquery cannot be result relation");
- }
-
- /*
- * for heap_formtuple to work, the targetlist must match the exact
- * order of the attributes. We also need to fill in any missing
- * attributes. -ay 10/94
- */
- if (command_type == CMD_INSERT || command_type == CMD_UPDATE)
- tlist = expand_targetlist(tlist, command_type,
- result_relation, range_table);
-
- /*
- * for "update" and "delete" queries, add ctid of the result relation
- * into the target list so that the ctid will propagate through
- * execution and ExecutePlan() will be able to identify the right
- * tuple to replace or delete. This extra field is marked "junk" so
- * that it is not stored back into the tuple.
- */
- if (command_type == CMD_UPDATE || command_type == CMD_DELETE)
- {
- Resdom *resdom;
- Var *var;
-
- resdom = makeResdom(length(tlist) + 1,
- TIDOID,
- -1,
- pstrdup("ctid"),
- true);
-
- var = makeVar(result_relation, SelfItemPointerAttributeNumber,
- TIDOID, -1, 0);
-
- /*
- * For an UPDATE, expand_targetlist already created a fresh tlist.
- * For DELETE, better do a listCopy so that we don't destructively
- * modify the original tlist (is this really necessary?).
- */
- if (command_type == CMD_DELETE)
- tlist = listCopy(tlist);
-
- tlist = lappend(tlist, makeTargetEntry(resdom, (Node *) var));
- }
-
- return tlist;
-}
-
-/*****************************************************************************
- *
- * TARGETLIST EXPANSION
- *
- *****************************************************************************/
-
-/*
- * expand_targetlist
- * Given a target list as generated by the parser and a result relation,
- * add targetlist entries for any missing attributes, and ensure the
- * non-junk attributes appear in proper field order.
- *
- * NOTE: if you are tempted to put more processing here, consider whether
- * it shouldn't go in the rewriter's rewriteTargetList() instead.
- */
-static List *
-expand_targetlist(List *tlist, int command_type,
- Index result_relation, List *range_table)
-{
- List *new_tlist = NIL;
- Relation rel;
- int attrno,
- numattrs;
-
- /*
- * The rewriter should have already ensured that the TLEs are in
- * correct order; but we have to insert TLEs for any missing attributes.
- *
- * Scan the tuple description in the relation's relcache entry to make
- * sure we have all the user attributes in the right order.
- */
- rel = heap_open(getrelid(result_relation, range_table), AccessShareLock);
-
- numattrs = RelationGetNumberOfAttributes(rel);
-
- for (attrno = 1; attrno <= numattrs; attrno++)
- {
- Form_pg_attribute att_tup = rel->rd_att->attrs[attrno - 1];
- TargetEntry *new_tle = NULL;
-
- if (tlist != NIL)
- {
- TargetEntry *old_tle = (TargetEntry *) lfirst(tlist);
- Resdom *resdom = old_tle->resdom;
-
- if (!resdom->resjunk && resdom->resno == attrno)
- {
- Assert(strcmp(resdom->resname,
- NameStr(att_tup->attname)) == 0);
- new_tle = old_tle;
- tlist = lnext(tlist);
- }
- }
-
- if (new_tle == NULL)
- {
- /*
- * Didn't find a matching tlist entry, so make one.
- *
- * For INSERT, generate a NULL constant. (We assume the
- * rewriter would have inserted any available default value.)
- *
- * For UPDATE, generate a Var reference to the existing value of
- * the attribute, so that it gets copied to the new tuple.
- */
- Oid atttype = att_tup->atttypid;
- int32 atttypmod = att_tup->atttypmod;
- Node *new_expr;
-
- switch (command_type)
- {
- case CMD_INSERT:
- new_expr = (Node *) makeConst(atttype,
- att_tup->attlen,
- (Datum) 0,
- true, /* isnull */
- att_tup->attbyval,
- false, /* not a set */
- false);
- break;
- case CMD_UPDATE:
- new_expr = (Node *) makeVar(result_relation,
- attrno,
- atttype,
- atttypmod,
- 0);
- break;
- default:
- elog(ERROR, "expand_targetlist: unexpected command_type");
- new_expr = NULL; /* keep compiler quiet */
- break;
- }
-
- new_tle = makeTargetEntry(makeResdom(attrno,
- atttype,
- atttypmod,
- pstrdup(NameStr(att_tup->attname)),
- false),
- new_expr);
- }
-
- new_tlist = lappend(new_tlist, new_tle);
- }
-
- /*
- * The remaining tlist entries should be resjunk; append them all to
- * the end of the new tlist, making sure they have resnos higher than
- * the last real attribute. (Note: although the rewriter already did
- * such renumbering, we have to do it again here in case we are doing
- * an UPDATE in an inheritance child table with more columns.)
- */
- while (tlist)
- {
- TargetEntry *old_tle = (TargetEntry *) lfirst(tlist);
- Resdom *resdom = old_tle->resdom;
-
- if (!resdom->resjunk)
- elog(ERROR, "expand_targetlist: targetlist is not sorted correctly");
- /* Get the resno right, but don't copy unnecessarily */
- if (resdom->resno != attrno)
- {
- resdom = (Resdom *) copyObject((Node *) resdom);
- resdom->resno = attrno;
- old_tle = makeTargetEntry(resdom, old_tle->expr);
- }
- new_tlist = lappend(new_tlist, old_tle);
- attrno++;
- tlist = lnext(tlist);
- }
-
- heap_close(rel, AccessShareLock);
-
- return new_tlist;
-}
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