Hi, On 10/03/26 14:53, Kirill Reshke wrote:
Today, while reviewing another patch, I spotted PostgreSQL behaviour which I cannot tell if is correct.-- create relation reshke=# create table pt (i int) partition by range ( i); CREATE TABLE -- create partitions. reshke=# create table pt1 partition of pt for values from ( 1 ) to (2) ; CREATE TABLE reshke=# create table pt2 partition of pt for values from ( 2 ) to (3) ; CREATE TABLE -- manually add dependency on extension. reshke=# alter index pt1_i_idx depends on extension btree_gist ; ALTER INDEX reshke=# alter index pt2_i_idx depends on extension btree_gist ; ALTER INDEX At this point, `drop extension btree_gist` fails due to existing dependencies. However, after `alter table pt merge partitions ( pt1 , pt2 ) into pt3;` there are no dependencies, and drop extension executes successfully. My first impression was that there is no issue as the user created a new database object, so should manually add dependency on extension. However I am not 100% in this reasoning. Any thoughts?
I'm also not sure if it's correct to assume that the dependency should be manually added after a partition is merged or splited but I was checking ATExecMergePartitions() and ATExecSplitPartition() and I think that it's not complicated to implement this.
IIUC we just need to collect the extension dependencies before an index is detached on MERGE and SPLIT operations and then apply the dependency after the index is created on the new merged/splited partition. The attached patch implement this.
Note that I'm using two different extensions for partition_merge and partition_split tests because I was having deadlock issues when running these tests in parallel using the same extension as a dependency.
-- Matheus Alcantara EDB: https://www.enterprisedb.com
From 72f1fe7d7ab1be5d41e6e66dac2c7cfcf4387be5 Mon Sep 17 00:00:00 2001 From: Matheus Alcantara <[email protected]> Date: Wed, 11 Mar 2026 11:39:56 -0300 Subject: [PATCH v1] Preserve extension dependencies on indexes during partition merge/split When using ALTER TABLE ... MERGE PARTITIONS or ALTER TABLE ... SPLIT PARTITION, extension dependencies on partition indexes (created via ALTER INDEX ... DEPENDS ON EXTENSION) were being lost. This happened because the new partition indexes are created fresh from the parent partitioned table's indexes, while the old partition indexes (with their extension dependencies) are dropped. Fix this by collecting extension dependencies from source partition indexes before detaching them, then applying those dependencies to the corresponding new partition indexes after they're created. The mapping between old and new indexes is done via their common parent partitioned index. Discussion: https://www.postgresql.org/message-id/CALdSSPjXtzGM7Uk4fWRwRMXcCczge5uNirPQcYCHKPAWPkp9iQ%40mail.gmail.com Reported-by: Kirill Reshke --- src/backend/commands/tablecmds.c | 218 ++++++++++++++++++ src/test/regress/expected/partition_merge.out | 40 ++++ src/test/regress/expected/partition_split.out | 41 ++++ src/test/regress/sql/partition_merge.sql | 38 +++ src/test/regress/sql/partition_split.sql | 39 ++++ src/tools/pgindent/typedefs.list | 1 + 6 files changed, 377 insertions(+) diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 85242dcc245..bbcdd20dedb 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -39,6 +39,7 @@ #include "catalog/pg_collation.h" #include "catalog/pg_constraint.h" #include "catalog/pg_depend.h" +#include "catalog/pg_extension_d.h" #include "catalog/pg_foreign_table.h" #include "catalog/pg_inherits.h" #include "catalog/pg_largeobject.h" @@ -358,6 +359,16 @@ typedef enum addFkConstraintSides addFkBothSides, } addFkConstraintSides; +/* + * Hold extension dependencies for a partitioned index. Used by + * collectPartitionIndexExtDeps and applyPartitionIndexExtDeps. + */ +typedef struct PartitionIndexExtDepEntry +{ + Oid parentIndexOid; /* OID of the parent partitioned index */ + List *extensionOids; /* List of extension OIDs this index depends */ +} PartitionIndexExtDepEntry; + /* * Partition tables are expected to be dropped when the parent partitioned * table gets dropped. Hence for partitioning we use AUTO dependency. @@ -745,6 +756,9 @@ static void ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation static void ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel, PartitionCmd *cmd, AlterTableUtilityContext *context); +static List *collectPartitionIndexExtDeps(List *partitionOids); +static void applyPartitionIndexExtDeps(Oid newPartOid, List *extDepState); +static void freePartitionIndexExtDeps(List *extDepState); /* ---------------------------------------------------------------- * DefineRelation @@ -22780,6 +22794,171 @@ detachPartitionTable(Relation parent_rel, Relation child_rel, Oid defaultPartOid PopActiveSnapshot(); } +/* + * collectPartitionIndexExtDeps: collect extension dependencies from indexes + * on the given partitions. + * + * For each index on the source partitions that has extension dependencies, we + * collect a mapping from the parent partitioned index OID to the list of + * extension OIDs. + * + * Returns a list of PartitionIndexExtDepEntry structs. + */ +static List * +collectPartitionIndexExtDeps(List *partitionOids) +{ + List *result = NIL; + + foreach_oid(partOid, partitionOids) + { + Relation partRel; + List *indexList; + + /* + * Use NoLock since the caller already holds AccessExclusiveLock on + * these partitions. + */ + partRel = table_open(partOid, NoLock); + indexList = RelationGetIndexList(partRel); + + foreach_oid(indexOid, indexList) + { + Oid parentIdxOid; + List *extDeps; + PartitionIndexExtDepEntry *entry = NULL; + ListCell *lc; + + /* Get the parent index if this is a partition index */ + parentIdxOid = get_partition_parent(indexOid, true); + if (!OidIsValid(parentIdxOid)) + continue; + + /* Get extension dependencies for this index */ + extDeps = getAutoExtensionsOfObject(RelationRelationId, indexOid); + if (extDeps == NIL) + continue; + + /* + * Look for existing entry for this parent index. + */ + foreach(lc, result) + { + PartitionIndexExtDepEntry *e = lfirst(lc); + + if (e->parentIndexOid == parentIdxOid) + { + entry = e; + break; + } + } + + if (entry != NULL) + { + /* Add extension dependencies avoiding duplicates */ + foreach_oid(extOid, extDeps) + { + if (!list_member_oid(entry->extensionOids, extOid)) + entry->extensionOids = lappend_oid(entry->extensionOids, + extOid); + } + list_free(extDeps); + } + else + { + /* Create new entry */ + entry = palloc(sizeof(PartitionIndexExtDepEntry)); + entry->parentIndexOid = parentIdxOid; + entry->extensionOids = extDeps; + result = lappend(result, entry); + } + } + + list_free(indexList); + table_close(partRel, NoLock); + } + + return result; +} + +/* + * applyPartitionIndexExtDeps: apply collected extension dependencies to + * indexes on a new partition. + * + * For each index on the new partition, look up its parent index in the + * extDepState list. If found, record extension dependencies on the new index. + */ +static void +applyPartitionIndexExtDeps(Oid newPartOid, List *extDepState) +{ + Relation partRel; + List *indexList; + + if (extDepState == NIL) + return; + + /* + * Use NoLock since the caller already holds AccessExclusiveLock on the + * new partition. + */ + partRel = table_open(newPartOid, NoLock); + indexList = RelationGetIndexList(partRel); + + foreach_oid(indexOid, indexList) + { + Oid parentIdxOid; + ListCell *lc; + + /* Get the parent index if this is a partition index */ + parentIdxOid = get_partition_parent(indexOid, true); + if (!OidIsValid(parentIdxOid)) + continue; + + /* Look for extension dependencies to apply */ + foreach(lc, extDepState) + { + PartitionIndexExtDepEntry *entry = lfirst(lc); + + if (entry->parentIndexOid == parentIdxOid) + { + ObjectAddress indexAddr; + + ObjectAddressSet(indexAddr, RelationRelationId, indexOid); + + foreach_oid(extOid, entry->extensionOids) + { + ObjectAddress extAddr; + + ObjectAddressSet(extAddr, ExtensionRelationId, extOid); + recordDependencyOn(&indexAddr, &extAddr, + DEPENDENCY_AUTO_EXTENSION); + } + break; + } + } + } + + list_free(indexList); + table_close(partRel, NoLock); +} + +/* + * freePartitionIndexExtDeps: free memory allocated by collectPartitionIndexExtDeps. + */ +static void +freePartitionIndexExtDeps(List *extDepState) +{ + ListCell *lc; + + foreach(lc, extDepState) + { + PartitionIndexExtDepEntry *entry = lfirst(lc); + + list_free(entry->extensionOids); + pfree(entry); + } + list_free(extDepState); +} + /* * ALTER TABLE <name> MERGE PARTITIONS <partition-list> INTO <partition-name> */ @@ -22789,6 +22968,7 @@ ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation rel, { Relation newPartRel; List *mergingPartitions = NIL; + List *extDepState = NIL; Oid defaultPartOid; Oid existingRelid; Oid ownerId = InvalidOid; @@ -22878,6 +23058,13 @@ ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation rel, defaultPartOid = get_default_oid_from_partdesc(RelationGetPartitionDesc(rel, true)); + /* + * Collect extension dependencies from indexes on the merging partitions. + * We must do this before detaching them, so we can restore the + * dependencies on the new partition's indexes later. + */ + extDepState = collectPartitionIndexExtDeps(mergingPartitions); + /* Detach all merging partitions. */ foreach_oid(mergingPartitionOid, mergingPartitions) { @@ -22955,6 +23142,15 @@ ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation rel, */ attachPartitionTable(NULL, rel, newPartRel, cmd->bound); + /* + * Apply extension dependencies to the new partition's indexes. This + * preserves any "DEPENDS ON EXTENSION" settings from the merged + * partitions. + */ + applyPartitionIndexExtDeps(RelationGetRelid(newPartRel), extDepState); + + freePartitionIndexExtDeps(extDepState); + /* Keep the lock until commit. */ table_close(newPartRel, NoLock); @@ -23248,11 +23444,13 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel, bool isSameName = false; char tmpRelName[NAMEDATALEN]; List *newPartRels = NIL; + List *extDepState = NIL; ObjectAddress object; Oid defaultPartOid; Oid save_userid; int save_sec_context; int save_nestlevel; + List *splitPartList; defaultPartOid = get_default_oid_from_partdesc(RelationGetPartitionDesc(rel, true)); @@ -23285,6 +23483,16 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel, errmsg("relation \"%s\" already exists", sps->name->relname)); } + /* + * Collect extension dependencies from indexes on the split partition. We + * must do this before detaching it, so we can restore the dependencies on + * the new partitions' indexes later. + */ + splitPartList = list_make1_oid(splitRelOid); + + extDepState = collectPartitionIndexExtDeps(splitPartList); + list_free(splitPartList); + /* Detach the split partition. */ detachPartitionTable(rel, splitRel, defaultPartOid); @@ -23364,10 +23572,20 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel, * needed. */ attachPartitionTable(NULL, rel, newPartRel, sps->bound); + + /* + * Apply extension dependencies to the new partition's indexes. This + * preserves any "DEPENDS ON EXTENSION" settings from the split + * partition. + */ + applyPartitionIndexExtDeps(RelationGetRelid(newPartRel), extDepState); + /* Keep the lock until commit. */ table_close(newPartRel, NoLock); } + freePartitionIndexExtDeps(extDepState); + /* Drop the split partition. */ object.classId = RelationRelationId; object.objectId = splitRelOid; diff --git a/src/test/regress/expected/partition_merge.out b/src/test/regress/expected/partition_merge.out index 925fe4f570a..00aa16964ce 100644 --- a/src/test/regress/expected/partition_merge.out +++ b/src/test/regress/expected/partition_merge.out @@ -1091,6 +1091,46 @@ SELECT count(*) FROM t WHERE i = 15 AND g IN (SELECT g + 10 FROM t WHERE i = 5); (1 row) DROP TABLE t; +-- +-- Test that extension dependencies on partition indexes are preserved +-- after MERGE PARTITIONS. +-- +CREATE EXTENSION if not exists btree_gist; +CREATE TABLE t_merge_extdep (i int) PARTITION BY RANGE (i); +CREATE TABLE t_merge_extdep_1 PARTITION OF t_merge_extdep FOR VALUES FROM (1) TO (2); +CREATE TABLE t_merge_extdep_2 PARTITION OF t_merge_extdep FOR VALUES FROM (2) TO (3); +CREATE INDEX t_merge_extdep_idx ON t_merge_extdep USING gist (i); +-- Add extension dependency on partition indexes +ALTER INDEX t_merge_extdep_1_i_idx DEPENDS ON EXTENSION btree_gist; +ALTER INDEX t_merge_extdep_2_i_idx DEPENDS ON EXTENSION btree_gist; +-- Should fail: dependencies exist +DROP EXTENSION btree_gist; +ERROR: cannot drop extension btree_gist because other objects depend on it +DETAIL: index t_merge_extdep_idx depends on operator class gist_int4_ops for access method gist +HINT: Use DROP ... CASCADE to drop the dependent objects too. +-- Merge partitions +ALTER TABLE t_merge_extdep MERGE PARTITIONS (t_merge_extdep_1, t_merge_extdep_2) INTO t_merge_extdep_merged; +-- Should still fail: dependencies should be preserved on the new partition's index +DROP EXTENSION btree_gist; +ERROR: cannot drop extension btree_gist because other objects depend on it +DETAIL: index t_merge_extdep_idx depends on operator class gist_int4_ops for access method gist +HINT: Use DROP ... CASCADE to drop the dependent objects too. +-- Verify the dependency exists in pg_depend +SELECT COUNT(*) > 0 AS has_ext_dep +FROM pg_depend d +JOIN pg_class c ON d.objid = c.oid +JOIN pg_extension e ON d.refobjid = e.oid +WHERE c.relname = 't_merge_extdep_merged_i_idx' + AND e.extname = 'btree_gist' + AND d.deptype = 'x'; + has_ext_dep +------------- + t +(1 row) + +-- Clean up +DROP TABLE t_merge_extdep; +DROP EXTENSION btree_gist; RESET search_path; -- DROP SCHEMA partitions_merge_schema; diff --git a/src/test/regress/expected/partition_split.out b/src/test/regress/expected/partition_split.out index 4004efe0dac..efb85674c37 100644 --- a/src/test/regress/expected/partition_split.out +++ b/src/test/regress/expected/partition_split.out @@ -1586,6 +1586,47 @@ SELECT count(*) FROM t WHERE i = 0 AND tab_id IN (SELECT tab_id FROM t WHERE i = (1 row) DROP TABLE t; +-- +-- Test that extension dependencies on partition indexes are preserved +-- after SPLIT PARTITION. +-- +CREATE EXTENSION citext; +CREATE TABLE t_extdep (i int) PARTITION BY RANGE (i); +CREATE TABLE t_extdep_1_3 PARTITION OF t_extdep FOR VALUES FROM (1) TO (3); +CREATE INDEX t_extdep_idx ON t_extdep (i); +-- Add extension dependency on partition index +ALTER INDEX t_extdep_1_3_i_idx DEPENDS ON EXTENSION citext; +-- Should fail: dependency exists +DROP EXTENSION citext; +ERROR: cannot drop index t_extdep_1_3_i_idx because index t_extdep_idx requires it +HINT: You can drop index t_extdep_idx instead. +-- Split partition +ALTER TABLE t_extdep SPLIT PARTITION t_extdep_1_3 INTO + (PARTITION t_extdep_1 FOR VALUES FROM (1) TO (2), + PARTITION t_extdep_2 FOR VALUES FROM (2) TO (3)); +-- Should still fail: dependencies should be preserved on all new partitions' indexes +DROP EXTENSION citext; +ERROR: cannot drop index t_extdep_2_i_idx because index t_extdep_idx requires it +HINT: You can drop index t_extdep_idx instead. +-- Verify the dependencies exist in pg_depend for both new partitions +SELECT c.relname, COUNT(*) > 0 AS has_ext_dep +FROM pg_depend d +JOIN pg_class c ON d.objid = c.oid +JOIN pg_extension e ON d.refobjid = e.oid +WHERE c.relname IN ('t_extdep_1_i_idx', 't_extdep_2_i_idx') + AND e.extname = 'citext' + AND d.deptype = 'x' +GROUP BY c.relname +ORDER BY c.relname; + relname | has_ext_dep +------------------+------------- + t_extdep_1_i_idx | t + t_extdep_2_i_idx | t +(2 rows) + +-- Clean up +DROP TABLE t_extdep; +DROP EXTENSION citext; RESET search_path; -- DROP SCHEMA partition_split_schema; diff --git a/src/test/regress/sql/partition_merge.sql b/src/test/regress/sql/partition_merge.sql index a211fee2ad1..4864c66636d 100644 --- a/src/test/regress/sql/partition_merge.sql +++ b/src/test/regress/sql/partition_merge.sql @@ -784,6 +784,44 @@ SELECT count(*) FROM t WHERE i = 15 AND g IN (SELECT g + 10 FROM t WHERE i = 5); DROP TABLE t; +-- +-- Test that extension dependencies on partition indexes are preserved +-- after MERGE PARTITIONS. +-- +CREATE EXTENSION if not exists btree_gist; + +CREATE TABLE t_merge_extdep (i int) PARTITION BY RANGE (i); +CREATE TABLE t_merge_extdep_1 PARTITION OF t_merge_extdep FOR VALUES FROM (1) TO (2); +CREATE TABLE t_merge_extdep_2 PARTITION OF t_merge_extdep FOR VALUES FROM (2) TO (3); +CREATE INDEX t_merge_extdep_idx ON t_merge_extdep USING gist (i); + +-- Add extension dependency on partition indexes +ALTER INDEX t_merge_extdep_1_i_idx DEPENDS ON EXTENSION btree_gist; +ALTER INDEX t_merge_extdep_2_i_idx DEPENDS ON EXTENSION btree_gist; + +-- Should fail: dependencies exist +DROP EXTENSION btree_gist; + +-- Merge partitions +ALTER TABLE t_merge_extdep MERGE PARTITIONS (t_merge_extdep_1, t_merge_extdep_2) INTO t_merge_extdep_merged; + +-- Should still fail: dependencies should be preserved on the new partition's index +DROP EXTENSION btree_gist; + +-- Verify the dependency exists in pg_depend +SELECT COUNT(*) > 0 AS has_ext_dep +FROM pg_depend d +JOIN pg_class c ON d.objid = c.oid +JOIN pg_extension e ON d.refobjid = e.oid +WHERE c.relname = 't_merge_extdep_merged_i_idx' + AND e.extname = 'btree_gist' + AND d.deptype = 'x'; + +-- Clean up +DROP TABLE t_merge_extdep; +DROP EXTENSION btree_gist; + + RESET search_path; -- diff --git a/src/test/regress/sql/partition_split.sql b/src/test/regress/sql/partition_split.sql index 37c6d730840..ea35aa591a8 100644 --- a/src/test/regress/sql/partition_split.sql +++ b/src/test/regress/sql/partition_split.sql @@ -1127,6 +1127,45 @@ SELECT count(*) FROM t WHERE i = 0 AND tab_id IN (SELECT tab_id FROM t WHERE i = DROP TABLE t; +-- +-- Test that extension dependencies on partition indexes are preserved +-- after SPLIT PARTITION. +-- +CREATE EXTENSION citext; + +CREATE TABLE t_extdep (i int) PARTITION BY RANGE (i); +CREATE TABLE t_extdep_1_3 PARTITION OF t_extdep FOR VALUES FROM (1) TO (3); +CREATE INDEX t_extdep_idx ON t_extdep (i); + +-- Add extension dependency on partition index +ALTER INDEX t_extdep_1_3_i_idx DEPENDS ON EXTENSION citext; + +-- Should fail: dependency exists +DROP EXTENSION citext; + +-- Split partition +ALTER TABLE t_extdep SPLIT PARTITION t_extdep_1_3 INTO + (PARTITION t_extdep_1 FOR VALUES FROM (1) TO (2), + PARTITION t_extdep_2 FOR VALUES FROM (2) TO (3)); + +-- Should still fail: dependencies should be preserved on all new partitions' indexes +DROP EXTENSION citext; + +-- Verify the dependencies exist in pg_depend for both new partitions +SELECT c.relname, COUNT(*) > 0 AS has_ext_dep +FROM pg_depend d +JOIN pg_class c ON d.objid = c.oid +JOIN pg_extension e ON d.refobjid = e.oid +WHERE c.relname IN ('t_extdep_1_i_idx', 't_extdep_2_i_idx') + AND e.extname = 'citext' + AND d.deptype = 'x' +GROUP BY c.relname +ORDER BY c.relname; + +-- Clean up +DROP TABLE t_extdep; +DROP EXTENSION citext; + RESET search_path; -- diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list index 3da19d41413..01c7715fe73 100644 --- a/src/tools/pgindent/typedefs.list +++ b/src/tools/pgindent/typedefs.list @@ -2150,6 +2150,7 @@ PartitionDirectoryEntry PartitionDispatch PartitionElem PartitionHashBound +PartitionIndexExtDepEntry PartitionKey PartitionListValue PartitionMap -- 2.52.0
