From e9e413b086fee0bb4e52fea782d4544c9729b0ba Mon Sep 17 00:00:00 2001 From: Alvaro Herrera Date: Thu, 26 Sep 2024 19:37:50 +0200 Subject: [PATCH v6 1/2] Don't disallow DROP of constraints ONLY on partitioned tables This restriction seems to have come about due to some fuzzy thinking. --- src/backend/commands/tablecmds.c | 34 ----------------------- src/test/regress/expected/alter_table.out | 9 ++---- src/test/regress/sql/alter_table.sql | 5 ++-- 3 files changed, 4 insertions(+), 44 deletions(-) diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 87232e0137..a45f456af5 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -447,7 +447,6 @@ static bool check_for_column_name_collision(Relation rel, const char *colname, bool if_not_exists); static void add_column_datatype_dependency(Oid relid, int32 attnum, Oid typid); static void add_column_collation_dependency(Oid relid, int32 attnum, Oid collid); -static void ATPrepDropNotNull(Relation rel, bool recurse, bool recursing); static ObjectAddress ATExecDropNotNull(Relation rel, const char *colName, LOCKMODE lockmode); static void ATPrepSetNotNull(List **wqueue, Relation rel, AlterTableCmd *cmd, bool recurse, bool recursing, @@ -4858,7 +4857,6 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd, case AT_DropNotNull: /* ALTER COLUMN DROP NOT NULL */ ATSimplePermissions(cmd->subtype, rel, ATT_TABLE | ATT_PARTITIONED_TABLE | ATT_FOREIGN_TABLE); - ATPrepDropNotNull(rel, recurse, recursing); ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode, context); pass = AT_PASS_DROP; break; @@ -7500,26 +7498,6 @@ add_column_collation_dependency(Oid relid, int32 attnum, Oid collid) * ALTER TABLE ALTER COLUMN DROP NOT NULL */ -static void -ATPrepDropNotNull(Relation rel, bool recurse, bool recursing) -{ - /* - * If the parent is a partitioned table, like check constraints, we do not - * support removing the NOT NULL while partitions exist. - */ - if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE) - { - PartitionDesc partdesc = RelationGetPartitionDesc(rel, true); - - Assert(partdesc != NULL); - if (partdesc->nparts > 0 && !recurse && !recursing) - ereport(ERROR, - (errcode(ERRCODE_INVALID_TABLE_DEFINITION), - errmsg("cannot remove constraint from only the partitioned table when partitions exist"), - errhint("Do not specify the ONLY keyword."))); - } -} - /* * Return the address of the modified column. If the column was already * nullable, InvalidObjectAddress is returned. @@ -12713,18 +12691,6 @@ ATExecDropConstraint(Relation rel, const char *constrName, else children = NIL; - /* - * For a partitioned table, if partitions exist and we are told not to - * recurse, it's a user error. It doesn't make sense to have a constraint - * be defined only on the parent, especially if it's a partitioned table. - */ - if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE && - children != NIL && !recurse) - ereport(ERROR, - (errcode(ERRCODE_INVALID_TABLE_DEFINITION), - errmsg("cannot remove constraint from only the partitioned table when partitions exist"), - errhint("Do not specify the ONLY keyword."))); - foreach_oid(childrelid, children) { Relation childrel; diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out index 3b3b0738d7..445d68d160 100644 --- a/src/test/regress/expected/alter_table.out +++ b/src/test/regress/expected/alter_table.out @@ -4401,7 +4401,7 @@ ALTER TABLE part_2 RENAME COLUMN b to c; ERROR: cannot rename inherited column "b" ALTER TABLE part_2 ALTER COLUMN b TYPE text; ERROR: cannot alter inherited column "b" --- cannot add/drop NOT NULL or check constraints to *only* the parent, when +-- cannot add NOT NULL or check constraints to *only* the parent, when -- partitions exist ALTER TABLE ONLY list_parted2 ALTER b SET NOT NULL; ERROR: constraint must be added to child tables too @@ -4409,20 +4409,15 @@ DETAIL: Column "b" of relation "part_2" is not already NOT NULL. HINT: Do not specify the ONLY keyword. ALTER TABLE ONLY list_parted2 ADD CONSTRAINT check_b CHECK (b <> 'zz'); ERROR: constraint must be added to child tables too +-- dropping them is ok though ALTER TABLE list_parted2 ALTER b SET NOT NULL; ALTER TABLE ONLY list_parted2 ALTER b DROP NOT NULL; -ERROR: cannot remove constraint from only the partitioned table when partitions exist -HINT: Do not specify the ONLY keyword. ALTER TABLE list_parted2 ADD CONSTRAINT check_b CHECK (b <> 'zz'); ALTER TABLE ONLY list_parted2 DROP CONSTRAINT check_b; -ERROR: cannot remove constraint from only the partitioned table when partitions exist -HINT: Do not specify the ONLY keyword. -- It's alright though, if no partitions are yet created CREATE TABLE parted_no_parts (a int) PARTITION BY LIST (a); ALTER TABLE ONLY parted_no_parts ALTER a SET NOT NULL; ALTER TABLE ONLY parted_no_parts ADD CONSTRAINT check_a CHECK (a > 0); -ALTER TABLE ONLY parted_no_parts ALTER a DROP NOT NULL; -ALTER TABLE ONLY parted_no_parts DROP CONSTRAINT check_a; DROP TABLE parted_no_parts; -- cannot drop inherited NOT NULL or check constraints from partition ALTER TABLE list_parted2 ALTER b SET NOT NULL, ADD CONSTRAINT check_a2 CHECK (a > 0); diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql index 453799abed..0eac8ed2e9 100644 --- a/src/test/regress/sql/alter_table.sql +++ b/src/test/regress/sql/alter_table.sql @@ -2815,11 +2815,12 @@ ALTER TABLE part_2 DROP COLUMN b; ALTER TABLE part_2 RENAME COLUMN b to c; ALTER TABLE part_2 ALTER COLUMN b TYPE text; --- cannot add/drop NOT NULL or check constraints to *only* the parent, when +-- cannot add NOT NULL or check constraints to *only* the parent, when -- partitions exist ALTER TABLE ONLY list_parted2 ALTER b SET NOT NULL; ALTER TABLE ONLY list_parted2 ADD CONSTRAINT check_b CHECK (b <> 'zz'); +-- dropping them is ok though ALTER TABLE list_parted2 ALTER b SET NOT NULL; ALTER TABLE ONLY list_parted2 ALTER b DROP NOT NULL; ALTER TABLE list_parted2 ADD CONSTRAINT check_b CHECK (b <> 'zz'); @@ -2829,8 +2830,6 @@ ALTER TABLE ONLY list_parted2 DROP CONSTRAINT check_b; CREATE TABLE parted_no_parts (a int) PARTITION BY LIST (a); ALTER TABLE ONLY parted_no_parts ALTER a SET NOT NULL; ALTER TABLE ONLY parted_no_parts ADD CONSTRAINT check_a CHECK (a > 0); -ALTER TABLE ONLY parted_no_parts ALTER a DROP NOT NULL; -ALTER TABLE ONLY parted_no_parts DROP CONSTRAINT check_a; DROP TABLE parted_no_parts; -- cannot drop inherited NOT NULL or check constraints from partition -- 2.39.2