From 0f296d8bef250e38eee74d58cbfc04e6c9c5ea7b Mon Sep 17 00:00:00 2001 From: "Chao Li (Evan)" Date: Thu, 14 May 2026 13:49:43 +0800 Subject: [PATCH v2 1/4] Fix SPLIT PARTITION range bound validation with DEFAULT When splitting a range partition and defining a new DEFAULT partition, the validation checked the lower bound of the first explicit partition and the upper bound of explicit partitions only when they were not first. If there was exactly one explicit non-DEFAULT partition, its upper bound was therefore not checked. This could allow the replacement partition to extend beyond the upper bound of the partition being split, potentially overlapping another existing partition. Fix this by checking the upper bound whenever the explicit partition is the last one. Add a regression test covering the single explicit partition plus DEFAULT case. Author: Chao Li Reviewed-by: Kirill Reshke Reviewed-by: Zhenwei Shang Reviewed-by: Dmitry Koval Discussion: https://postgr.es/m/C18878AB-DEB2-4A61-9995-A035DD644B81@gmail.com --- src/backend/partitioning/partbounds.c | 3 ++- src/test/regress/expected/partition_split.out | 16 ++++++++++++++++ src/test/regress/sql/partition_split.sql | 15 +++++++++++++++ 3 files changed, 33 insertions(+), 1 deletion(-) diff --git a/src/backend/partitioning/partbounds.c b/src/backend/partitioning/partbounds.c index a09beec34d8..73dea0375be 100644 --- a/src/backend/partitioning/partbounds.c +++ b/src/backend/partitioning/partbounds.c @@ -5419,7 +5419,8 @@ check_partition_bounds_for_split_range(Relation parent, "ALTER TABLE ... SPLIT PARTITION"), parser_errposition(pstate, exprLocation((Node *) datum))); } - else + + if (last) { PartitionRangeBound *split_upper; diff --git a/src/test/regress/expected/partition_split.out b/src/test/regress/expected/partition_split.out index 961b37953c8..a2ccbe5138b 100644 --- a/src/test/regress/expected/partition_split.out +++ b/src/test/regress/expected/partition_split.out @@ -1188,6 +1188,22 @@ SELECT tableoid::regclass, * FROM sales_range ORDER BY tableoid::regclass::text DROP TABLE sales_range; -- +-- Test that the explicit partition bound cannot extend outside the split +-- partition's bound when a DEFAULT partition is specified. +-- +CREATE TABLE t (i int) PARTITION BY RANGE (i); +CREATE TABLE tp_0_51 PARTITION OF t FOR VALUES FROM (0) TO (51); +CREATE TABLE tp_51_100 PARTITION OF t FOR VALUES FROM (51) TO (100); +-- ERROR +ALTER TABLE t SPLIT PARTITION tp_0_51 INTO + (PARTITION tp_0_51 FOR VALUES FROM (0) TO (53), + PARTITION tp_default DEFAULT); +ERROR: upper bound of partition "tp_0_51" is greater than upper bound of split partition "tp_0_51" +LINE 2: (PARTITION tp_0_51 FOR VALUES FROM (0) TO (53), + ^ +HINT: ALTER TABLE ... SPLIT PARTITION require combined bounds of new partitions must exactly match the bound of the split partition. +DROP TABLE t; +-- -- Try to SPLIT partition of another table. -- CREATE TABLE t1(i int, t text) PARTITION BY LIST (t); diff --git a/src/test/regress/sql/partition_split.sql b/src/test/regress/sql/partition_split.sql index a110fc87867..d9821c5e2a3 100644 --- a/src/test/regress/sql/partition_split.sql +++ b/src/test/regress/sql/partition_split.sql @@ -834,6 +834,21 @@ SELECT tableoid::regclass, * FROM sales_range ORDER BY tableoid::regclass::text DROP TABLE sales_range; +-- +-- Test that the explicit partition bound cannot extend outside the split +-- partition's bound when a DEFAULT partition is specified. +-- +CREATE TABLE t (i int) PARTITION BY RANGE (i); +CREATE TABLE tp_0_51 PARTITION OF t FOR VALUES FROM (0) TO (51); +CREATE TABLE tp_51_100 PARTITION OF t FOR VALUES FROM (51) TO (100); + +-- ERROR +ALTER TABLE t SPLIT PARTITION tp_0_51 INTO + (PARTITION tp_0_51 FOR VALUES FROM (0) TO (53), + PARTITION tp_default DEFAULT); + +DROP TABLE t; + -- -- Try to SPLIT partition of another table. -- -- 2.50.1 (Apple Git-155)