diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 1bd9bef3e723e47b66d24c5a413137f007a84208..f88bf793e57e60f98a73fcf1de5a750d34cdb5b0 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -335,13 +335,15 @@ static void ATExecAddIndex(AlteredTableInfo *tab, Relation rel,
IndexStmt *stmt, bool is_rebuild, LOCKMODE lockmode);
static void ATExecAddConstraint(List **wqueue,
AlteredTableInfo *tab, Relation rel,
- Constraint *newConstraint, bool recurse, LOCKMODE lockmode);
+ Constraint *newConstraint, bool recurse, bool is_readd,
+ LOCKMODE lockmode);
static void ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
IndexStmt *stmt, LOCKMODE lockmode);
static void ATAddCheckConstraint(List **wqueue,
AlteredTableInfo *tab, Relation rel,
Constraint *constr,
- bool recurse, bool recursing, LOCKMODE lockmode);
+ bool recurse, bool recursing, bool is_readd,
+ LOCKMODE lockmode);
static void ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
Constraint *fkconstraint, LOCKMODE lockmode);
static void ATExecDropConstraint(Relation rel, const char *constrName,
@@ -2758,6 +2760,7 @@ AlterTableGetLockLevel(List *cmds)
case AT_ColumnDefault:
case AT_ProcessedConstraint: /* becomes AT_AddConstraint */
case AT_AddConstraintRecurse: /* becomes AT_AddConstraint */
+ case AT_ReAddConstraint: /* becomes AT_AddConstraint */
case AT_EnableTrig:
case AT_EnableAlwaysTrig:
case AT_EnableReplicaTrig:
@@ -3249,11 +3252,15 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
break;
case AT_AddConstraint: /* ADD CONSTRAINT */
ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
- false, lockmode);
+ false, false, lockmode);
break;
case AT_AddConstraintRecurse: /* ADD CONSTRAINT with recursion */
ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
- true, lockmode);
+ true, false, lockmode);
+ break;
+ case AT_ReAddConstraint: /* Re-add pre-existing check constraint */
+ ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
+ false, true, lockmode);
break;
case AT_AddIndexConstraint: /* ADD CONSTRAINT USING INDEX */
ATExecAddIndexConstraint(tab, rel, (IndexStmt *) cmd->def, lockmode);
@@ -5500,7 +5507,8 @@ ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
*/
static void
ATExecAddConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
- Constraint *newConstraint, bool recurse, LOCKMODE lockmode)
+ Constraint *newConstraint, bool recurse, bool is_readd,
+ LOCKMODE lockmode)
{
Assert(IsA(newConstraint, Constraint));
@@ -5513,7 +5521,8 @@ ATExecAddConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
{
case CONSTR_CHECK:
ATAddCheckConstraint(wqueue, tab, rel,
- newConstraint, recurse, false, lockmode);
+ newConstraint, recurse, false, is_readd,
+ lockmode);
break;
case CONSTR_FOREIGN:
@@ -5565,11 +5574,18 @@ ATExecAddConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
* AddRelationNewConstraints would normally assign different names to the
* child constraints. To fix that, we must capture the name assigned at
* the parent table and pass that down.
+ *
+ * When re-adding a previously existing constraint (during ALTER COLUMN TYPE),
+ * we don't need to recurse here, because recursion will be carried out at a
+ * higher level; the constraint name issue doesn't apply because the names
+ * have already been assigned and are just being re-used. We need a separate
+ * "is_readd" flag for that; just setting recurse=false would result in an
+ * error if there are child tables.
*/
static void
ATAddCheckConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
Constraint *constr, bool recurse, bool recursing,
- LOCKMODE lockmode)
+ bool is_readd, LOCKMODE lockmode)
{
List *newcons;
ListCell *lcon;
@@ -5634,9 +5650,11 @@ ATAddCheckConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
return;
/*
- * Adding a NO INHERIT constraint? No need to find our children
+ * If adding a NO INHERIT constraint, no need to find our children.
+ * Likewise, in a re-add operation, we don't need to recurse (that will be
+ * handled at higher levels).
*/
- if (constr->is_no_inherit)
+ if (constr->is_no_inherit || is_readd)
return;
/*
@@ -5671,7 +5689,7 @@ ATAddCheckConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
/* Recurse to child */
ATAddCheckConstraint(wqueue, childtab, childrel,
- constr, recurse, true, lockmode);
+ constr, recurse, true, is_readd, lockmode);
heap_close(childrel, NoLock);
}
@@ -7862,6 +7880,10 @@ ATPostAlterTypeParse(Oid oldId, char *cmd,
/*
* Attach each generated command to the proper place in the work queue.
* Note this could result in creation of entirely new work-queue entries.
+ *
+ * Also note that we have to tweak the command subtypes, because it turns
+ * out that re-creation of indexes and constraints has to act a bit
+ * differently from initial creation.
*/
foreach(list_item, querytree_list)
{
@@ -7919,6 +7941,7 @@ ATPostAlterTypeParse(Oid oldId, char *cmd,
if (con->contype == CONSTR_FOREIGN &&
!rewrite && !tab->rewrite)
TryReuseForeignKey(oldId, con);
+ cmd->subtype = AT_ReAddConstraint;
tab->subcmds[AT_PASS_OLD_CONSTR] =
lappend(tab->subcmds[AT_PASS_OLD_CONSTR], cmd);
break;
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 09b15e7694cde1932b3640a8bb8f69e7606ea6b9..88344990f47e04578a3d267d930d588e7aab5cd4 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -1197,6 +1197,7 @@ typedef enum AlterTableType
AT_ReAddIndex, /* internal to commands/tablecmds.c */
AT_AddConstraint, /* add constraint */
AT_AddConstraintRecurse, /* internal to commands/tablecmds.c */
+ AT_ReAddConstraint, /* internal to commands/tablecmds.c */
AT_ValidateConstraint, /* validate constraint */
AT_ValidateConstraintRecurse, /* internal to commands/tablecmds.c */
AT_ProcessedConstraint, /* pre-processed add constraint (local in
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index c22d74c7b562e86d6e839b4ab3a87d3cf7a29149..8392c27b368d6db70a1c9d379487d27eb86c844a 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -1780,6 +1780,28 @@ where oid = 'test_storage'::regclass;
t
(1 row)
+-- ALTER TYPE with a check constraint and a child table (bug before Nov 2012)
+CREATE TABLE test_inh_check (a float check (a > 10.2));
+CREATE TABLE test_inh_check_child() INHERITS(test_inh_check);
+ALTER TABLE test_inh_check ALTER COLUMN a TYPE numeric;
+\d test_inh_check
+Table "public.test_inh_check"
+ Column | Type | Modifiers
+--------+---------+-----------
+ a | numeric |
+Check constraints:
+ "test_inh_check_a_check" CHECK (a::double precision > 10.2::double precision)
+Number of child tables: 1 (Use \d+ to list them.)
+
+\d test_inh_check_child
+Table "public.test_inh_check_child"
+ Column | Type | Modifiers
+--------+---------+-----------
+ a | numeric |
+Check constraints:
+ "test_inh_check_a_check" CHECK (a::double precision > 10.2::double precision)
+Inherits: test_inh_check
+
--
-- lock levels
--
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index 0f9cb380e1662749295cc2fca959346a8d1b84c6..dcf8121d70c1dd7ac2db2ffaf58ce20bca2ec742 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -1239,6 +1239,13 @@ select reltoastrelid <> 0 as has_toast_table
from pg_class
where oid = 'test_storage'::regclass;
+-- ALTER TYPE with a check constraint and a child table (bug before Nov 2012)
+CREATE TABLE test_inh_check (a float check (a > 10.2));
+CREATE TABLE test_inh_check_child() INHERITS(test_inh_check);
+ALTER TABLE test_inh_check ALTER COLUMN a TYPE numeric;
+\d test_inh_check
+\d test_inh_check_child
+
--
-- lock levels
--