database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-07 00:36:50 +03:00
Code Activity

Disallow partitionwise join when collations don't match

Browse Source 
If the collation of any join key column doesn’t match the collation of
the corresponding partition key, partitionwise joins can yield incorrect
results. For example, rows that would match under the join key collation
might be located in different partitions due to the partitioning
collation. In such cases, a partitionwise join would yield different
results from a non-partitionwise join, so disallow it in such cases.

Reported-by: Tender Wang <tndrwang@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/CAHewXNno_HKiQ6PqyLYfuqDtwp7KKHZiH1J7Pqyz0nr+PS2Dwg@mail.gmail.com
Backpatch-through: 12
This commit is contained in:
Amit Langote
2024-11-08 16:27:24 +09:00
parent 90fe6251c8
commit 075acdd933
3 changed files with 324 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
src/backend/optimizer/util/relnode.c
View File

@ -2185,6 +2185,10 @@ have_partkey_equi_join(PlannerInfo *root, RelOptInfo *joinrel,
if (pk_known_equal[ipk1])
continue;
/* Reject if the partition key collation differs from the clause's. */
if (rel1->part_scheme->partcollation[ipk1] != opexpr->inputcollid)
return false;
/*
* The clause allows partitionwise join only if it uses the same
* operator family as that specified by the partition key.
@ -2258,6 +2262,8 @@ have_partkey_equi_join(PlannerInfo *root, RelOptInfo *joinrel,
{
Node *expr1 = (Node *) lfirst(lc);
ListCell *lc2;
Oid partcoll1 = rel1->part_scheme->partcollation[ipk];
Oid exprcoll1 = exprCollation(expr1);
foreach(lc2, rel2->partexprs[ipk])
{
@ -2265,10 +2271,28 @@ have_partkey_equi_join(PlannerInfo *root, RelOptInfo *joinrel,
if (exprs_known_equal(root, expr1, expr2, btree_opfamily))
{
/*
* Ensure that the collation of the expression matches
* that of the partition key. Checking just one collation
* (partcoll1 and exprcoll1) suffices because partcoll1
* and partcoll2, as well as exprcoll1 and exprcoll2,
* should be identical. This holds because both rel1 and
* rel2 use the same PartitionScheme and expr1 and expr2
* are equal.
*/
if (partcoll1 == exprcoll1)
{
Oid partcoll2 PG_USED_FOR_ASSERTS_ONLY =
rel2->part_scheme->partcollation[ipk];
Oid exprcoll2 PG_USED_FOR_ASSERTS_ONLY =
exprCollation(expr2);
Assert(partcoll2 == exprcoll2);
pk_known_equal[ipk] = true;
break;
}
}
}
if (pk_known_equal[ipk])
break;
}

234
src/test/regress/expected/collate.icu.utf8.out
View File

@ -2140,7 +2140,241 @@ SELECT c collate "C", count(c) FROM pagg_tab3 GROUP BY c collate "C" ORDER BY 1;
b | 5
(4 rows)
-- Partitionwise join should not be allowed too when the collation used by the
-- join keys doesn't match the partition key collation.
SET enable_partitionwise_join TO false;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c GROUP BY 1 ORDER BY t1.c COLLATE "C";
QUERY PLAN
-------------------------------------------------------------
Sort
Sort Key: t1.c COLLATE "C"
-> HashAggregate
Group Key: t1.c
-> Hash Join
Hash Cond: (t1.c = t2.c)
-> Append
-> Seq Scan on pagg_tab3_p2 t1_1
-> Seq Scan on pagg_tab3_p1 t1_2
-> Hash
-> Append
-> Seq Scan on pagg_tab3_p2 t2_1
-> Seq Scan on pagg_tab3_p1 t2_2
(13 rows)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c GROUP BY 1 ORDER BY t1.c COLLATE "C";
c | count
---+-------
A | 100
B | 100
(2 rows)
SET enable_partitionwise_join TO true;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c GROUP BY 1 ORDER BY t1.c COLLATE "C";
QUERY PLAN
-------------------------------------------------------------
Sort
Sort Key: t1.c COLLATE "C"
-> HashAggregate
Group Key: t1.c
-> Hash Join
Hash Cond: (t1.c = t2.c)
-> Append
-> Seq Scan on pagg_tab3_p2 t1_1
-> Seq Scan on pagg_tab3_p1 t1_2
-> Hash
-> Append
-> Seq Scan on pagg_tab3_p2 t2_1
-> Seq Scan on pagg_tab3_p1 t2_2
(13 rows)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c GROUP BY 1 ORDER BY t1.c COLLATE "C";
c | count
---+-------
A | 100
B | 100
(2 rows)
-- OK when the join clause uses the same collation as the partition key.
EXPLAIN (COSTS OFF)
SELECT t1.c COLLATE "C", count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c COLLATE "C" GROUP BY t1.c COLLATE "C" ORDER BY t1.c COLLATE "C";
QUERY PLAN
------------------------------------------------------------------
Sort
Sort Key: ((t1.c)::text) COLLATE "C"
-> Append
-> HashAggregate
Group Key: (t1.c)::text
-> Hash Join
Hash Cond: ((t1.c)::text = (t2.c)::text)
-> Seq Scan on pagg_tab3_p2 t1
-> Hash
-> Seq Scan on pagg_tab3_p2 t2
-> HashAggregate
Group Key: (t1_1.c)::text
-> Hash Join
Hash Cond: ((t1_1.c)::text = (t2_1.c)::text)
-> Seq Scan on pagg_tab3_p1 t1_1
-> Hash
-> Seq Scan on pagg_tab3_p1 t2_1
(17 rows)
SELECT t1.c COLLATE "C", count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c COLLATE "C" GROUP BY t1.c COLLATE "C" ORDER BY t1.c COLLATE "C";
c | count
---+-------
A | 25
B | 25
a | 25
b | 25
(4 rows)
SET enable_partitionwise_join TO false;
EXPLAIN (COSTS OFF)
SELECT t1.c COLLATE "C", count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c COLLATE "C" GROUP BY t1.c COLLATE "C" ORDER BY t1.c COLLATE "C";
QUERY PLAN
-------------------------------------------------------------
Sort
Sort Key: ((t1.c)::text) COLLATE "C"
-> HashAggregate
Group Key: (t1.c)::text
-> Hash Join
Hash Cond: ((t1.c)::text = (t2.c)::text)
-> Append
-> Seq Scan on pagg_tab3_p2 t1_1
-> Seq Scan on pagg_tab3_p1 t1_2
-> Hash
-> Append
-> Seq Scan on pagg_tab3_p2 t2_1
-> Seq Scan on pagg_tab3_p1 t2_2
(13 rows)
SELECT t1.c COLLATE "C", count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c COLLATE "C" GROUP BY t1.c COLLATE "C" ORDER BY t1.c COLLATE "C";
c | count
---+-------
A | 25
B | 25
a | 25
b | 25
(4 rows)
-- Few other cases where the joined partition keys are matched via equivalence
-- class, not a join restriction clause.
-- Collations of joined columns match, but the partition keys collation is different
SET enable_partitionwise_join TO true;
CREATE TABLE pagg_tab4 (c text collate case_insensitive, b text collate case_insensitive) PARTITION BY LIST (b collate "C");
CREATE TABLE pagg_tab4_p1 PARTITION OF pagg_tab4 FOR VALUES IN ('a', 'b');
CREATE TABLE pagg_tab4_p2 PARTITION OF pagg_tab4 FOR VALUES IN ('B', 'A');
INSERT INTO pagg_tab4 (b, c) SELECT substr('abAB', (i % 4) + 1 , 1), substr('abAB', (i % 2) + 1 , 1) FROM generate_series(0, 11) i;
ANALYZE pagg_tab4;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab4 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
QUERY PLAN
-------------------------------------------------------------
Sort
Sort Key: t1.c COLLATE "C"
-> HashAggregate
Group Key: t1.c
-> Hash Join
Hash Cond: (t1.c = t2.c)
-> Append
-> Seq Scan on pagg_tab3_p2 t1_1
-> Seq Scan on pagg_tab3_p1 t1_2
-> Hash
-> Append
-> Seq Scan on pagg_tab4_p2 t2_1
Filter: (c = b)
-> Seq Scan on pagg_tab4_p1 t2_2
Filter: (c = b)
(15 rows)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab4 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
c | count
---+-------
A | 60
B | 60
(2 rows)
-- OK when the partition key collation is same as that of the join columns
CREATE TABLE pagg_tab5 (c text collate case_insensitive, b text collate case_insensitive) PARTITION BY LIST (c collate case_insensitive);
CREATE TABLE pagg_tab5_p1 PARTITION OF pagg_tab5 FOR VALUES IN ('a', 'b');
CREATE TABLE pagg_tab5_p2 PARTITION OF pagg_tab5 FOR VALUES IN ('c', 'd');
INSERT INTO pagg_tab5 (b, c) SELECT substr('abAB', (i % 4) + 1 , 1), substr('abAB', (i % 2) + 1 , 1) FROM generate_series(0, 5) i;
INSERT INTO pagg_tab5 (b, c) SELECT substr('cdCD', (i % 4) + 1 , 1), substr('cdCD', (i % 2) + 1 , 1) FROM generate_series(0, 5) i;
ANALYZE pagg_tab5;
CREATE TABLE pagg_tab6 (c text collate case_insensitive, b text collate case_insensitive) PARTITION BY LIST (b collate case_insensitive);
CREATE TABLE pagg_tab6_p1 PARTITION OF pagg_tab6 FOR VALUES IN ('a', 'b');
CREATE TABLE pagg_tab6_p2 PARTITION OF pagg_tab6 FOR VALUES IN ('c', 'd');
INSERT INTO pagg_tab6 (b, c) SELECT substr('abAB', (i % 4) + 1 , 1), substr('abAB', (i % 2) + 1 , 1) FROM generate_series(0, 5) i;
INSERT INTO pagg_tab6 (b, c) SELECT substr('cdCD', (i % 4) + 1 , 1), substr('cdCD', (i % 2) + 1 , 1) FROM generate_series(0, 5) i;
ANALYZE pagg_tab6;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab5 t1 JOIN pagg_tab6 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
QUERY PLAN
-------------------------------------------------------
Sort
Sort Key: t1.c COLLATE "C"
-> Append
-> HashAggregate
Group Key: t1.c
-> Nested Loop
Join Filter: (t1.c = t2.c)
-> Seq Scan on pagg_tab6_p1 t2
Filter: (c = b)
-> Seq Scan on pagg_tab5_p1 t1
-> HashAggregate
Group Key: t1_1.c
-> Nested Loop
Join Filter: (t1_1.c = t2_1.c)
-> Seq Scan on pagg_tab6_p2 t2_1
Filter: (c = b)
-> Seq Scan on pagg_tab5_p2 t1_1
(17 rows)
SELECT t1.c, count(t2.c) FROM pagg_tab5 t1 JOIN pagg_tab6 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
c | count
---+-------
a | 9
b | 9
c | 9
d | 9
(4 rows)
SET enable_partitionwise_join TO false;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab5 t1 JOIN pagg_tab6 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
QUERY PLAN
-------------------------------------------------------------
Sort
Sort Key: t1.c COLLATE "C"
-> HashAggregate
Group Key: t1.c
-> Hash Join
Hash Cond: (t1.c = t2.c)
-> Append
-> Seq Scan on pagg_tab5_p1 t1_1
-> Seq Scan on pagg_tab5_p2 t1_2
-> Hash
-> Append
-> Seq Scan on pagg_tab6_p1 t2_1
Filter: (c = b)
-> Seq Scan on pagg_tab6_p2 t2_2
Filter: (c = b)
(15 rows)
SELECT t1.c, count(t2.c) FROM pagg_tab5 t1 JOIN pagg_tab6 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
c | count
---+-------
a | 9
b | 9
c | 9
d | 9
(4 rows)
DROP TABLE pagg_tab3;
DROP TABLE pagg_tab4;
DROP TABLE pagg_tab5;
DROP TABLE pagg_tab6;
RESET enable_partitionwise_aggregate;
RESET max_parallel_workers_per_gather;
RESET enable_incremental_sort;

64
src/test/regress/sql/collate.icu.utf8.sql
View File

@ -828,7 +828,71 @@ EXPLAIN (COSTS OFF)
SELECT c collate "C", count(c) FROM pagg_tab3 GROUP BY c collate "C" ORDER BY 1;
SELECT c collate "C", count(c) FROM pagg_tab3 GROUP BY c collate "C" ORDER BY 1;
-- Partitionwise join should not be allowed too when the collation used by the
-- join keys doesn't match the partition key collation.
SET enable_partitionwise_join TO false;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c GROUP BY 1 ORDER BY t1.c COLLATE "C";
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c GROUP BY 1 ORDER BY t1.c COLLATE "C";
SET enable_partitionwise_join TO true;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c GROUP BY 1 ORDER BY t1.c COLLATE "C";
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c GROUP BY 1 ORDER BY t1.c COLLATE "C";
-- OK when the join clause uses the same collation as the partition key.
EXPLAIN (COSTS OFF)
SELECT t1.c COLLATE "C", count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c COLLATE "C" GROUP BY t1.c COLLATE "C" ORDER BY t1.c COLLATE "C";
SELECT t1.c COLLATE "C", count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c COLLATE "C" GROUP BY t1.c COLLATE "C" ORDER BY t1.c COLLATE "C";
SET enable_partitionwise_join TO false;
EXPLAIN (COSTS OFF)
SELECT t1.c COLLATE "C", count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c COLLATE "C" GROUP BY t1.c COLLATE "C" ORDER BY t1.c COLLATE "C";
SELECT t1.c COLLATE "C", count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab3 t2 ON t1.c = t2.c COLLATE "C" GROUP BY t1.c COLLATE "C" ORDER BY t1.c COLLATE "C";
-- Few other cases where the joined partition keys are matched via equivalence
-- class, not a join restriction clause.
-- Collations of joined columns match, but the partition keys collation is different
SET enable_partitionwise_join TO true;
CREATE TABLE pagg_tab4 (c text collate case_insensitive, b text collate case_insensitive) PARTITION BY LIST (b collate "C");
CREATE TABLE pagg_tab4_p1 PARTITION OF pagg_tab4 FOR VALUES IN ('a', 'b');
CREATE TABLE pagg_tab4_p2 PARTITION OF pagg_tab4 FOR VALUES IN ('B', 'A');
INSERT INTO pagg_tab4 (b, c) SELECT substr('abAB', (i % 4) + 1 , 1), substr('abAB', (i % 2) + 1 , 1) FROM generate_series(0, 11) i;
ANALYZE pagg_tab4;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab4 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
SELECT t1.c, count(t2.c) FROM pagg_tab3 t1 JOIN pagg_tab4 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
-- OK when the partition key collation is same as that of the join columns
CREATE TABLE pagg_tab5 (c text collate case_insensitive, b text collate case_insensitive) PARTITION BY LIST (c collate case_insensitive);
CREATE TABLE pagg_tab5_p1 PARTITION OF pagg_tab5 FOR VALUES IN ('a', 'b');
CREATE TABLE pagg_tab5_p2 PARTITION OF pagg_tab5 FOR VALUES IN ('c', 'd');
INSERT INTO pagg_tab5 (b, c) SELECT substr('abAB', (i % 4) + 1 , 1), substr('abAB', (i % 2) + 1 , 1) FROM generate_series(0, 5) i;
INSERT INTO pagg_tab5 (b, c) SELECT substr('cdCD', (i % 4) + 1 , 1), substr('cdCD', (i % 2) + 1 , 1) FROM generate_series(0, 5) i;
ANALYZE pagg_tab5;
CREATE TABLE pagg_tab6 (c text collate case_insensitive, b text collate case_insensitive) PARTITION BY LIST (b collate case_insensitive);
CREATE TABLE pagg_tab6_p1 PARTITION OF pagg_tab6 FOR VALUES IN ('a', 'b');
CREATE TABLE pagg_tab6_p2 PARTITION OF pagg_tab6 FOR VALUES IN ('c', 'd');
INSERT INTO pagg_tab6 (b, c) SELECT substr('abAB', (i % 4) + 1 , 1), substr('abAB', (i % 2) + 1 , 1) FROM generate_series(0, 5) i;
INSERT INTO pagg_tab6 (b, c) SELECT substr('cdCD', (i % 4) + 1 , 1), substr('cdCD', (i % 2) + 1 , 1) FROM generate_series(0, 5) i;
ANALYZE pagg_tab6;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab5 t1 JOIN pagg_tab6 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
SELECT t1.c, count(t2.c) FROM pagg_tab5 t1 JOIN pagg_tab6 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
SET enable_partitionwise_join TO false;
EXPLAIN (COSTS OFF)
SELECT t1.c, count(t2.c) FROM pagg_tab5 t1 JOIN pagg_tab6 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
SELECT t1.c, count(t2.c) FROM pagg_tab5 t1 JOIN pagg_tab6 t2 ON t1.c = t2.c AND t1.c = t2.b GROUP BY 1 ORDER BY t1.c COLLATE "C";
DROP TABLE pagg_tab3;
DROP TABLE pagg_tab4;
DROP TABLE pagg_tab5;
DROP TABLE pagg_tab6;
RESET enable_partitionwise_aggregate;
RESET max_parallel_workers_per_gather;