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-rw-r--r--src/backend/executor/nodeValuesscan.c110
-rw-r--r--src/include/nodes/execnodes.h10
-rw-r--r--src/test/regress/expected/subselect.out27
-rw-r--r--src/test/regress/sql/subselect.sql14
4 files changed, 118 insertions, 43 deletions
diff --git a/src/backend/executor/nodeValuesscan.c b/src/backend/executor/nodeValuesscan.c
index 8d916a0303d..88661217e9c 100644
--- a/src/backend/executor/nodeValuesscan.c
+++ b/src/backend/executor/nodeValuesscan.c
@@ -26,6 +26,7 @@
#include "executor/executor.h"
#include "executor/nodeValuesscan.h"
#include "jit/jit.h"
+#include "optimizer/clauses.h"
#include "utils/expandeddatum.h"
@@ -50,7 +51,7 @@ ValuesNext(ValuesScanState *node)
EState *estate;
ExprContext *econtext;
ScanDirection direction;
- List *exprlist;
+ int curr_idx;
/*
* get information from the estate and scan state
@@ -67,19 +68,11 @@ ValuesNext(ValuesScanState *node)
{
if (node->curr_idx < node->array_len)
node->curr_idx++;
- if (node->curr_idx < node->array_len)
- exprlist = node->exprlists[node->curr_idx];
- else
- exprlist = NIL;
}
else
{
if (node->curr_idx >= 0)
node->curr_idx--;
- if (node->curr_idx >= 0)
- exprlist = node->exprlists[node->curr_idx];
- else
- exprlist = NIL;
}
/*
@@ -90,16 +83,16 @@ ValuesNext(ValuesScanState *node)
*/
ExecClearTuple(slot);
- if (exprlist)
+ curr_idx = node->curr_idx;
+ if (curr_idx >= 0 && curr_idx < node->array_len)
{
+ List *exprlist = node->exprlists[curr_idx];
+ List *exprstatelist = node->exprstatelists[curr_idx];
MemoryContext oldContext;
- List *oldsubplans;
- List *exprstatelist;
Datum *values;
bool *isnull;
ListCell *lc;
int resind;
- int saved_jit_flags;
/*
* Get rid of any prior cycle's leftovers. We use ReScanExprContext
@@ -109,38 +102,32 @@ ValuesNext(ValuesScanState *node)
ReScanExprContext(econtext);
/*
- * Build the expression eval state in the econtext's per-tuple memory.
- * This is a tad unusual, but we want to delete the eval state again
- * when we move to the next row, to avoid growth of memory
- * requirements over a long values list.
+ * Do per-VALUES-row work in the per-tuple context.
*/
oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
/*
- * The expressions might contain SubPlans (this is currently only
- * possible if there's a sub-select containing a LATERAL reference,
- * otherwise sub-selects in a VALUES list should be InitPlans). Those
- * subplans will want to hook themselves into our subPlan list, which
- * would result in a corrupted list after we delete the eval state. We
- * can work around this by saving and restoring the subPlan list.
- * (There's no need for the functionality that would be enabled by
- * having the list entries, since the SubPlans aren't going to be
- * re-executed anyway.)
- */
- oldsubplans = node->ss.ps.subPlan;
- node->ss.ps.subPlan = NIL;
-
- /*
- * As the expressions are only ever used once, disable JIT for them.
- * This is worthwhile because it's common to insert significant
- * amounts of data via VALUES().
+ * Unless we already made the expression eval state for this row,
+ * build it in the econtext's per-tuple memory. This is a tad
+ * unusual, but we want to delete the eval state again when we move to
+ * the next row, to avoid growth of memory requirements over a long
+ * values list. For rows in which that won't work, we already built
+ * the eval state at plan startup.
*/
- saved_jit_flags = econtext->ecxt_estate->es_jit_flags;
- econtext->ecxt_estate->es_jit_flags = PGJIT_NONE;
- exprstatelist = ExecInitExprList(exprlist, &node->ss.ps);
- econtext->ecxt_estate->es_jit_flags = saved_jit_flags;
-
- node->ss.ps.subPlan = oldsubplans;
+ if (exprstatelist == NIL)
+ {
+ /*
+ * Pass parent as NULL, not my plan node, because we don't want
+ * anything in this transient state linking into permanent state.
+ * The only expression type that might wish to do so is a SubPlan,
+ * and we already checked that there aren't any.
+ *
+ * Note that passing parent = NULL also disables JIT compilation
+ * of the expressions, which is a win, because they're only going
+ * to be used once under normal circumstances.
+ */
+ exprstatelist = ExecInitExprList(exprlist, NULL);
+ }
/* parser should have checked all sublists are the same length */
Assert(list_length(exprstatelist) == slot->tts_tupleDescriptor->natts);
@@ -281,13 +268,52 @@ ExecInitValuesScan(ValuesScan *node, EState *estate, int eflags)
scanstate->curr_idx = -1;
scanstate->array_len = list_length(node->values_lists);
- /* convert list of sublists into array of sublists for easy addressing */
+ /*
+ * Convert the list of expression sublists into an array for easier
+ * addressing at runtime. Also, detect whether any sublists contain
+ * SubPlans; for just those sublists, go ahead and do expression
+ * initialization. (This avoids problems with SubPlans wanting to connect
+ * themselves up to the outer plan tree. Notably, EXPLAIN won't see the
+ * subplans otherwise; also we will have troubles with dangling pointers
+ * and/or leaked resources if we try to handle SubPlans the same as
+ * simpler expressions.)
+ */
scanstate->exprlists = (List **)
palloc(scanstate->array_len * sizeof(List *));
+ scanstate->exprstatelists = (List **)
+ palloc0(scanstate->array_len * sizeof(List *));
i = 0;
foreach(vtl, node->values_lists)
{
- scanstate->exprlists[i++] = (List *) lfirst(vtl);
+ List *exprs = castNode(List, lfirst(vtl));
+
+ scanstate->exprlists[i] = exprs;
+
+ /*
+ * We can avoid the cost of a contain_subplans() scan in the simple
+ * case where there are no SubPlans anywhere.
+ */
+ if (estate->es_subplanstates &&
+ contain_subplans((Node *) exprs))
+ {
+ int saved_jit_flags;
+
+ /*
+ * As these expressions are only used once, disable JIT for them.
+ * This is worthwhile because it's common to insert significant
+ * amounts of data via VALUES(). Note that this doesn't prevent
+ * use of JIT *within* a subplan, since that's initialized
+ * separately; this just affects the upper-level subexpressions.
+ */
+ saved_jit_flags = estate->es_jit_flags;
+ estate->es_jit_flags = PGJIT_NONE;
+
+ scanstate->exprstatelists[i] = ExecInitExprList(exprs,
+ &scanstate->ss.ps);
+
+ estate->es_jit_flags = saved_jit_flags;
+ }
+ i++;
}
return scanstate;
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index eaea1f3b0c2..1f6f5bbc207 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -1670,7 +1670,8 @@ typedef struct FunctionScanState
*
* rowcontext per-expression-list context
* exprlists array of expression lists being evaluated
- * array_len size of array
+ * exprstatelists array of expression state lists, for SubPlans only
+ * array_len size of above arrays
* curr_idx current array index (0-based)
*
* Note: ss.ps.ps_ExprContext is used to evaluate any qual or projection
@@ -1678,6 +1679,12 @@ typedef struct FunctionScanState
* rowcontext, in which to build the executor expression state for each
* Values sublist. Resetting this context lets us get rid of expression
* state for each row, avoiding major memory leakage over a long values list.
+ * However, that doesn't work for sublists containing SubPlans, because a
+ * SubPlan has to be connected up to the outer plan tree to work properly.
+ * Therefore, for only those sublists containing SubPlans, we do expression
+ * state construction at executor start, and store those pointers in
+ * exprstatelists[]. NULL entries in that array correspond to simple
+ * subexpressions that are handled as described above.
* ----------------
*/
typedef struct ValuesScanState
@@ -1685,6 +1692,7 @@ typedef struct ValuesScanState
ScanState ss; /* its first field is NodeTag */
ExprContext *rowcontext;
List **exprlists;
+ List **exprstatelists;
int array_len;
int curr_idx;
} ValuesScanState;
diff --git a/src/test/regress/expected/subselect.out b/src/test/regress/expected/subselect.out
index 547686166a6..71a677b7680 100644
--- a/src/test/regress/expected/subselect.out
+++ b/src/test/regress/expected/subselect.out
@@ -926,6 +926,33 @@ where s.i < 10 and (select val.x) < 110;
10
(17 rows)
+-- another variant of that (bug #16213)
+explain (verbose, costs off)
+select * from
+(values
+ (3 not in (select * from (values (1), (2)) ss1)),
+ (false)
+) ss;
+ QUERY PLAN
+----------------------------------------
+ Values Scan on "*VALUES*"
+ Output: "*VALUES*".column1
+ SubPlan 1
+ -> Values Scan on "*VALUES*_1"
+ Output: "*VALUES*_1".column1
+(5 rows)
+
+select * from
+(values
+ (3 not in (select * from (values (1), (2)) ss1)),
+ (false)
+) ss;
+ column1
+---------
+ t
+ f
+(2 rows)
+
--
-- Check sane behavior with nested IN SubLinks
--
diff --git a/src/test/regress/sql/subselect.sql b/src/test/regress/sql/subselect.sql
index 3e119ce1274..bd8d2f63d80 100644
--- a/src/test/regress/sql/subselect.sql
+++ b/src/test/regress/sql/subselect.sql
@@ -518,6 +518,20 @@ select val.x
) as val(x)
where s.i < 10 and (select val.x) < 110;
+-- another variant of that (bug #16213)
+explain (verbose, costs off)
+select * from
+(values
+ (3 not in (select * from (values (1), (2)) ss1)),
+ (false)
+) ss;
+
+select * from
+(values
+ (3 not in (select * from (values (1), (2)) ss1)),
+ (false)
+) ss;
+
--
-- Check sane behavior with nested IN SubLinks
--
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-31 17:11:18 +0000