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Promote row expressions to full-fledged citizens of the expression syntax,

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rather than allowing them only in a few special cases as before.  In
particular you can now pass a ROW() construct to a function that accepts
a rowtype parameter.  Internal generation of RowExprs fixes a number of
corner cases that used to not work very well, such as referencing the
whole-row result of a JOIN or subquery.  This represents a further step in
the work I started a month or so back to make rowtype values into
first-class citizens.
This commit is contained in:
Tom Lane
2004-05-10 22:44:49 +00:00
parent 9a939886ac
commit 2f63232d30
34 changed files with 1281 additions and 551 deletions
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50
src/backend/optimizer/prep/prepjointree.c
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@ -16,7 +16,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.16 2004/01/10 18:13:53 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.17 2004/05/10 22:44:45 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -45,7 +45,8 @@ typedef struct reduce_outer_joins_state
static bool is_simple_subquery(Query *subquery);
static bool has_nullable_targetlist(Query *subquery);
static void resolvenew_in_jointree(Node *jtnode, int varno, List *subtlist);
static void resolvenew_in_jointree(Node *jtnode, int varno,
RangeTblEntry *rte, List *subtlist);
static reduce_outer_joins_state *reduce_outer_joins_pass1(Node *jtnode);
static void reduce_outer_joins_pass2(Node *jtnode,
reduce_outer_joins_state *state,
@ -154,14 +155,10 @@ pull_up_subqueries(Query *parse, Node *jtnode, bool below_outer_join)
* such expressions; we'd have to figure out how to get the pseudo-
* variables evaluated at the right place in the modified plan
* tree. Fix it someday.
*
* Note: even if the subquery itself is simple enough, we can't pull
* it up if there is a reference to its whole tuple result.
* Perhaps a pseudo-variable is the answer here too.
*/
if (rte->rtekind == RTE_SUBQUERY && is_simple_subquery(subquery) &&
(!below_outer_join || has_nullable_targetlist(subquery)) &&
!contain_whole_tuple_var((Node *) parse, varno, 0))
if (rte->rtekind == RTE_SUBQUERY &&
is_simple_subquery(subquery) &&
(!below_outer_join || has_nullable_targetlist(subquery)))
{
int rtoffset;
List *subtlist;
@ -206,8 +203,7 @@ pull_up_subqueries(Query *parse, Node *jtnode, bool below_outer_join)
* the one above.
*/
if (is_simple_subquery(subquery) &&
(!below_outer_join || has_nullable_targetlist(subquery)) &&
!contain_whole_tuple_var((Node *) parse, varno, 0))
(!below_outer_join || has_nullable_targetlist(subquery)))
{
/* good to go */
}
@ -247,24 +243,25 @@ pull_up_subqueries(Query *parse, Node *jtnode, bool below_outer_join)
subtlist = subquery->targetList;
parse->targetList = (List *)
ResolveNew((Node *) parse->targetList,
varno, 0, subtlist, CMD_SELECT, 0);
resolvenew_in_jointree((Node *) parse->jointree, varno, subtlist);
varno, 0, rte, subtlist, CMD_SELECT, 0);
resolvenew_in_jointree((Node *) parse->jointree, varno,
rte, subtlist);
Assert(parse->setOperations == NULL);
parse->havingQual =
ResolveNew(parse->havingQual,
varno, 0, subtlist, CMD_SELECT, 0);
varno, 0, rte, subtlist, CMD_SELECT, 0);
parse->in_info_list = (List *)
ResolveNew((Node *) parse->in_info_list,
varno, 0, subtlist, CMD_SELECT, 0);
varno, 0, rte, subtlist, CMD_SELECT, 0);
foreach(rt, parse->rtable)
{
RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt);
RangeTblEntry *otherrte = (RangeTblEntry *) lfirst(rt);
if (rte->rtekind == RTE_JOIN)
rte->joinaliasvars = (List *)
ResolveNew((Node *) rte->joinaliasvars,
varno, 0, subtlist, CMD_SELECT, 0);
if (otherrte->rtekind == RTE_JOIN)
otherrte->joinaliasvars = (List *)
ResolveNew((Node *) otherrte->joinaliasvars,
varno, 0, rte, subtlist, CMD_SELECT, 0);
}
/*
@ -479,7 +476,8 @@ has_nullable_targetlist(Query *subquery)
* but there's no other way...
*/
static void
resolvenew_in_jointree(Node *jtnode, int varno, List *subtlist)
resolvenew_in_jointree(Node *jtnode, int varno,
RangeTblEntry *rte, List *subtlist)
{
if (jtnode == NULL)
return;
@ -493,18 +491,18 @@ resolvenew_in_jointree(Node *jtnode, int varno, List *subtlist)
List *l;
foreach(l, f->fromlist)
resolvenew_in_jointree(lfirst(l), varno, subtlist);
resolvenew_in_jointree(lfirst(l), varno, rte, subtlist);
f->quals = ResolveNew(f->quals,
varno, 0, subtlist, CMD_SELECT, 0);
varno, 0, rte, subtlist, CMD_SELECT, 0);
}
else if (IsA(jtnode, JoinExpr))
{
JoinExpr *j = (JoinExpr *) jtnode;
resolvenew_in_jointree(j->larg, varno, subtlist);
resolvenew_in_jointree(j->rarg, varno, subtlist);
resolvenew_in_jointree(j->larg, varno, rte, subtlist);
resolvenew_in_jointree(j->rarg, varno, rte, subtlist);
j->quals = ResolveNew(j->quals,
varno, 0, subtlist, CMD_SELECT, 0);
varno, 0, rte, subtlist, CMD_SELECT, 0);
/*
* We don't bother to update the colvars list, since it won't be