<listitem>
<para>
This form alters the attributes of a constraint that was previously
- created. Currently only foreign key constraints may be altered in
- this fashion, but see below.
+ created. Currently <literal>FOREIGN KEY</literal> and <literal>CHECK</literal>
+ constraints may be altered in this fashion, but see below.
</para>
</listitem>
</varlistentry>
Oid ReferencedParentUpdTrigger,
Oid ReferencingParentInsTrigger,
Oid ReferencingParentUpdTrigger);
+static bool ATExecAlterCheckConstrEnforceability(List **wqueue, ATAlterConstraint *cmdcon,
+ Relation conrel, HeapTuple contuple,
+ bool recurse, bool recursing,
+ LOCKMODE lockmode);
static bool ATExecAlterConstrDeferrability(List **wqueue, ATAlterConstraint *cmdcon,
Relation conrel, Relation tgrel, Relation rel,
HeapTuple contuple, bool recurse,
Oid ReferencedParentUpdTrigger,
Oid ReferencingParentInsTrigger,
Oid ReferencingParentUpdTrigger);
+static void AlterCheckConstrEnforceabilityRecurse(List **wqueue, ATAlterConstraint *cmdcon,
+ Relation conrel, Oid conrelid,
+ bool recurse, bool recursing,
+ LOCKMODE lockmode);
static void AlterConstrDeferrabilityRecurse(List **wqueue, ATAlterConstraint *cmdcon,
Relation conrel, Relation tgrel, Relation rel,
HeapTuple contuple, bool recurse,
*
* Update the attributes of a constraint.
*
- * Currently only works for Foreign Key and not null constraints.
+ * Currently works for Foreign Key, Check, and not null constraints.
*
* If the constraint is modified, returns its address; otherwise, return
* InvalidObjectAddress.
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("constraint \"%s\" of relation \"%s\" is not a foreign key constraint",
cmdcon->conname, RelationGetRelationName(rel))));
- if (cmdcon->alterEnforceability && currcon->contype != CONSTRAINT_FOREIGN)
+ if (cmdcon->alterEnforceability &&
+ (currcon->contype != CONSTRAINT_FOREIGN && currcon->contype != CONSTRAINT_CHECK))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot alter enforceability of constraint \"%s\" of relation \"%s\"",
- cmdcon->conname, RelationGetRelationName(rel))));
+ cmdcon->conname, RelationGetRelationName(rel)),
+ errhint("Only foreign key and check constraints can change enforceability.")));
if (cmdcon->alterInheritability &&
currcon->contype != CONSTRAINT_NOTNULL)
ereport(ERROR,
* dropping the trigger, during which the deferrability setting will be
* adjusted automatically.
*/
- if (cmdcon->alterEnforceability &&
- ATExecAlterFKConstrEnforceability(wqueue, cmdcon, conrel, tgrel,
- currcon->conrelid, currcon->confrelid,
- contuple, lockmode, InvalidOid,
- InvalidOid, InvalidOid, InvalidOid))
- changed = true;
-
+ if (cmdcon->alterEnforceability)
+ {
+ if (currcon->contype == CONSTRAINT_FOREIGN)
+ changed = ATExecAlterFKConstrEnforceability(wqueue, cmdcon, conrel, tgrel,
+ currcon->conrelid,
+ currcon->confrelid,
+ contuple, lockmode,
+ InvalidOid, InvalidOid,
+ InvalidOid, InvalidOid);
+ else if (currcon->contype == CONSTRAINT_CHECK)
+ changed = ATExecAlterCheckConstrEnforceability(wqueue, cmdcon, conrel,
+ contuple, recurse, false,
+ lockmode);
+ }
else if (cmdcon->alterDeferrability &&
ATExecAlterConstrDeferrability(wqueue, cmdcon, conrel, tgrel, rel,
contuple, recurse, &otherrelids,
return changed;
}
+/*
+ * Returns true if the CHECK constraint's enforceability is altered.
+ */
+static bool
+ATExecAlterCheckConstrEnforceability(List **wqueue, ATAlterConstraint *cmdcon,
+ Relation conrel, HeapTuple contuple,
+ bool recurse, bool recursing, LOCKMODE lockmode)
+{
+ Form_pg_constraint currcon;
+ Relation rel;
+ bool changed = false;
+ List *children = NIL;
+
+ /* Since this function recurses, it could be driven to stack overflow */
+ check_stack_depth();
+
+ Assert(cmdcon->alterEnforceability);
+
+ currcon = (Form_pg_constraint) GETSTRUCT(contuple);
+
+ Assert(currcon->contype == CONSTRAINT_CHECK);
+
+ /*
+ * Parent relation already locked by caller, children will be locked by
+ * find_all_inheritors. So NoLock is fine here.
+ */
+ rel = table_open(currcon->conrelid, NoLock);
+
+ if (currcon->conenforced != cmdcon->is_enforced)
+ {
+ AlterConstrUpdateConstraintEntry(cmdcon, conrel, contuple);
+ changed = true;
+ }
+
+ /*
+ * Note that we must recurse even when trying to change a check constraint
+ * to not enforced if it is already not enforced, in case descendant
+ * constraints might be enforced and need to be changed to not enforced.
+ * Conversely, we should do nothing if a constraint is being set to
+ * enforced and is already enforced, as descendant constraints cannot be
+ * different in that case.
+ */
+ if (!cmdcon->is_enforced || changed)
+ {
+ /*
+ * If we're recursing, the parent has already done this, so skip it.
+ * Also, if the constraint is a NO INHERIT constraint, we shouldn't
+ * try to look for it in the children.
+ */
+ if (!recursing && !currcon->connoinherit)
+ children = find_all_inheritors(RelationGetRelid(rel),
+ lockmode, NULL);
+
+ foreach_oid(childoid, children)
+ {
+ if (childoid == RelationGetRelid(rel))
+ continue;
+
+ /*
+ * If we are told not to recurse, there had better not be any
+ * child tables, because we can't change constraint enforceability
+ * on the parent unless we have changed enforceability for all
+ * child.
+ */
+ if (!recurse)
+ ereport(ERROR,
+ errcode(ERRCODE_INVALID_TABLE_DEFINITION),
+ errmsg("constraint must be altered on child tables too"),
+ errhint("Do not specify the ONLY keyword."));
+
+ AlterCheckConstrEnforceabilityRecurse(wqueue, cmdcon, conrel,
+ childoid, false, true,
+ lockmode);
+ }
+ }
+
+ /*
+ * Tell Phase 3 to check that the constraint is satisfied by existing
+ * rows. We only need do this when altering the constraint from NOT
+ * ENFORCED to ENFORCED.
+ */
+ if (rel->rd_rel->relkind == RELKIND_RELATION &&
+ !currcon->conenforced &&
+ cmdcon->is_enforced)
+ {
+ AlteredTableInfo *tab;
+ NewConstraint *newcon;
+ Datum val;
+ char *conbin;
+
+ newcon = palloc0_object(NewConstraint);
+ newcon->name = pstrdup(NameStr(currcon->conname));
+ newcon->contype = CONSTR_CHECK;
+
+ val = SysCacheGetAttrNotNull(CONSTROID, contuple,
+ Anum_pg_constraint_conbin);
+ conbin = TextDatumGetCString(val);
+ newcon->qual = expand_generated_columns_in_expr(stringToNode(conbin), rel, 1);
+
+ /* Find or create work queue entry for this table */
+ tab = ATGetQueueEntry(wqueue, rel);
+ tab->constraints = lappend(tab->constraints, newcon);
+ }
+
+ table_close(rel, NoLock);
+
+ return changed;
+}
+
+/*
+ * Invokes ATExecAlterCheckConstrEnforceability for each CHECK constraint that
+ * is a child of the specified constraint.
+ *
+ * We rely on the parent and child tables having identical CHECK constraint
+ * names to retrieve the child's pg_constraint tuple.
+ *
+ * The arguments to this function have the same meaning as the arguments to
+ * ATExecAlterCheckConstrEnforceability.
+ */
+static void
+AlterCheckConstrEnforceabilityRecurse(List **wqueue, ATAlterConstraint *cmdcon,
+ Relation conrel, Oid conrelid,
+ bool recurse, bool recursing,
+ LOCKMODE lockmode)
+{
+ SysScanDesc pscan;
+ HeapTuple childtup;
+ ScanKeyData skey[3];
+
+ ScanKeyInit(&skey[0],
+ Anum_pg_constraint_conrelid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum(conrelid));
+ ScanKeyInit(&skey[1],
+ Anum_pg_constraint_contypid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum(InvalidOid));
+ ScanKeyInit(&skey[2],
+ Anum_pg_constraint_conname,
+ BTEqualStrategyNumber, F_NAMEEQ,
+ CStringGetDatum(cmdcon->conname));
+
+ pscan = systable_beginscan(conrel, ConstraintRelidTypidNameIndexId, true,
+ NULL, 3, skey);
+
+ if (!HeapTupleIsValid(childtup = systable_getnext(pscan)))
+ ereport(ERROR,
+ errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("constraint \"%s\" of relation \"%s\" does not exist",
+ cmdcon->conname, get_rel_name(conrelid)));
+
+ ATExecAlterCheckConstrEnforceability(wqueue, cmdcon, conrel, childtup,
+ recurse, recursing, lockmode);
+
+ systable_endscan(pscan);
+}
+
/*
* Returns true if the constraint's deferrability is altered.
*
6 | OK | 4
(2 rows)
+--
+-- CHECK constraints
+-- ALTER TABLE ALTER CONSTRAINT [NOT] ENFORCED
+create table parted_ch(
+ a int, b int,
+ constraint cc check (a > 10) not enforced,
+ constraint cc_1 check (b < 17) not enforced
+) partition by range(a);
+create table parted_ch_1 partition of parted_ch for values from (0) to (10) partition by list(b);
+create table parted_ch_11 partition of parted_ch_1 for values in (0, 1, 22,4);
+create table parted_ch_12 partition of parted_ch_1 for values in (2);
+create table parted_ch_2(b int, a int,
+ constraint cc check (a > 10) not enforced,
+ constraint cc_1 check (b < 17) enforced,
+ constraint cc_2 check( a < 15) not enforced
+);
+alter table parted_ch attach partition parted_ch_2 for values from (10) to (20);
+insert into parted_ch values (1, 22), (9, 1), (16, 16);
+alter table parted_ch alter constraint cc_1 enforced; --error
+ERROR: check constraint "cc_1" of relation "parted_ch_11" is violated by some row
+update parted_ch set b = 4 where b = 22;
+alter table parted_ch alter constraint cc_1 enforced; --ok
+create or replace view check_constraint_status as
+select conname, conrelid::regclass, conenforced, convalidated
+from pg_constraint
+where conrelid::regclass::text ~* '^parted_ch' and contype = 'c'
+order by conname, conrelid::regclass::text collate "C";
+alter table parted_ch alter constraint cc not enforced; --no-op
+alter table parted_ch alter constraint cc enforced; --error
+ERROR: check constraint "cc" of relation "parted_ch_11" is violated by some row
+delete from parted_ch where a = 1;
+alter table parted_ch alter constraint cc enforced; --error
+ERROR: check constraint "cc" of relation "parted_ch_11" is violated by some row
+delete from parted_ch where a = 9;
+alter table parted_ch alter constraint cc enforced;
+--check these CHECK constraint status
+select * from check_constraint_status;
+ conname | conrelid | conenforced | convalidated
+---------+--------------+-------------+--------------
+ cc | parted_ch | t | t
+ cc | parted_ch_1 | t | t
+ cc | parted_ch_11 | t | t
+ cc | parted_ch_12 | t | t
+ cc | parted_ch_2 | t | t
+ cc_1 | parted_ch | t | t
+ cc_1 | parted_ch_1 | t | t
+ cc_1 | parted_ch_11 | t | t
+ cc_1 | parted_ch_12 | t | t
+ cc_1 | parted_ch_2 | t | t
+ cc_2 | parted_ch_2 | f | f
+(11 rows)
+
+alter table parted_ch_2 alter constraint cc_2 enforced; --error
+ERROR: check constraint "cc_2" of relation "parted_ch_2" is violated by some row
+delete from parted_ch where a = 16;
+alter table parted_ch_2 alter constraint cc_2 enforced;
+alter table parted_ch_2 alter constraint cc not enforced;
+alter table parted_ch_2 alter constraint cc_1 not enforced;
+alter table parted_ch_2 alter constraint cc_2 not enforced;
+--check these CHECK constraint status again
+select * from check_constraint_status;
+ conname | conrelid | conenforced | convalidated
+---------+--------------+-------------+--------------
+ cc | parted_ch | t | t
+ cc | parted_ch_1 | t | t
+ cc | parted_ch_11 | t | t
+ cc | parted_ch_12 | t | t
+ cc | parted_ch_2 | f | f
+ cc_1 | parted_ch | t | t
+ cc_1 | parted_ch_1 | t | t
+ cc_1 | parted_ch_11 | t | t
+ cc_1 | parted_ch_12 | t | t
+ cc_1 | parted_ch_2 | f | f
+ cc_2 | parted_ch_2 | f | f
+(11 rows)
+
+drop table parted_ch;
+drop view check_constraint_status;
--
-- Primary keys
--
^
ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key ENFORCED;
ERROR: cannot alter enforceability of constraint "unique_tbl_i_key" of relation "unique_tbl"
+HINT: Only foreign key and check constraints can change enforceability.
ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT ENFORCED;
ERROR: cannot alter enforceability of constraint "unique_tbl_i_key" of relation "unique_tbl"
+HINT: Only foreign key and check constraints can change enforceability.
-- can't make an existing constraint NOT VALID
ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT VALID;
ERROR: constraints cannot be altered to be NOT VALID
p1_c3 | inh_check_constraint9 | f | 2 | t | t
(38 rows)
+--
+-- CHECK constraints
+-- ALTER TABLE ALTER CONSTRAINT [NOT] ENFORCED
+alter table p1 drop constraint inh_check_constraint1;
+alter table p1_c1 drop constraint inh_check_constraint1;
+alter table only p1 alter constraint inh_check_constraint3 enforced; --error
+ERROR: constraint must be altered on child tables too
+HINT: Do not specify the ONLY keyword.
+alter table only p1 alter constraint inh_check_constraint3 not enforced; --error
+ERROR: constraint must be altered on child tables too
+HINT: Do not specify the ONLY keyword.
+insert into p1_c1 values(-2);
+insert into p1_c3 values(-3);
+alter table p1 alter constraint inh_check_constraint3 enforced; --error
+ERROR: check constraint "inh_check_constraint3" of relation "p1_c1" is violated by some row
+delete from only p1_c1 where f1 = -2;
+alter table p1_c1 alter constraint inh_check_constraint3 enforced; --error
+ERROR: check constraint "inh_check_constraint3" of relation "p1_c3" is violated by some row
+delete from only p1_c3 where f1 = -3;
+alter table p1 alter constraint inh_check_constraint3 enforced; --ok
+alter table p1 alter constraint inh_check_constraint3 not enforced; --ok
+select conname, conenforced, convalidated, conrelid::regclass
+from pg_constraint
+where conname = 'inh_check_constraint3' and contype = 'c'
+order by conrelid::regclass::text collate "C";
+ conname | conenforced | convalidated | conrelid
+-----------------------+-------------+--------------+----------
+ inh_check_constraint3 | f | f | p1
+ inh_check_constraint3 | f | f | p1_c1
+ inh_check_constraint3 | f | f | p1_c2
+ inh_check_constraint3 | f | f | p1_c3
+(4 rows)
+
drop table p1 cascade;
NOTICE: drop cascades to 3 other objects
DETAIL: drop cascades to table p1_c1
drop cascades to table p1_c2
drop cascades to table p1_c3
+--for "no inherit" check constraint, it will not recurse to child table
+create table p1(f1 int constraint p1_a_check check (f1 > 0) no inherit not enforced);
+create table p1_c1(f1 int constraint p1_a_check check (f1 > 0) not enforced);
+alter table p1_c1 inherit p1;
+insert into p1_c1 values(-11);
+alter table p1 alter constraint p1_a_check enforced; --ok
+alter table p1_c1 alter constraint p1_a_check enforced; --error
+ERROR: check constraint "p1_a_check" of relation "p1_c1" is violated by some row
+drop table p1 cascade;
+NOTICE: drop cascades to table p1_c1
--
-- Similarly, check the merging of existing constraints; a parent constraint
-- marked as NOT ENFORCED can merge with an ENFORCED child constraint, but the
create table p1(f1 int constraint p1_a_check check (f1 > 0) not enforced);
create table p1_c1(f1 int constraint p1_a_check check (f1 > 0) enforced);
alter table p1_c1 inherit p1;
+insert into p1 values(-1); --ok
+insert into p1_c1 values(-1); --error
+ERROR: new row for relation "p1_c1" violates check constraint "p1_a_check"
+DETAIL: Failing row contains (-1).
+alter table p1 alter constraint p1_a_check enforced; --error
+ERROR: check constraint "p1_a_check" of relation "p1" is violated by some row
+truncate p1;
+alter table p1 alter constraint p1_a_check enforced; --ok
+alter table p1 alter constraint p1_a_check not enforced; --ok
+select conname, conenforced, convalidated, conrelid::regclass
+from pg_constraint
+where conname = 'p1_a_check' and contype = 'c'
+order by conrelid::regclass::text collate "C";
+ conname | conenforced | convalidated | conrelid
+------------+-------------+--------------+----------
+ p1_a_check | f | f | p1
+ p1_a_check | f | f | p1_c1
+(2 rows)
+
drop table p1 cascade;
NOTICE: drop cascades to table p1_c1
create table p1(f1 int constraint p1_a_check check (f1 > 0) enforced);
SELECT * FROM COPY_TBL;
+--
+-- CHECK constraints
+-- ALTER TABLE ALTER CONSTRAINT [NOT] ENFORCED
+create table parted_ch(
+ a int, b int,
+ constraint cc check (a > 10) not enforced,
+ constraint cc_1 check (b < 17) not enforced
+) partition by range(a);
+create table parted_ch_1 partition of parted_ch for values from (0) to (10) partition by list(b);
+create table parted_ch_11 partition of parted_ch_1 for values in (0, 1, 22,4);
+create table parted_ch_12 partition of parted_ch_1 for values in (2);
+create table parted_ch_2(b int, a int,
+ constraint cc check (a > 10) not enforced,
+ constraint cc_1 check (b < 17) enforced,
+ constraint cc_2 check( a < 15) not enforced
+);
+alter table parted_ch attach partition parted_ch_2 for values from (10) to (20);
+
+insert into parted_ch values (1, 22), (9, 1), (16, 16);
+
+alter table parted_ch alter constraint cc_1 enforced; --error
+update parted_ch set b = 4 where b = 22;
+alter table parted_ch alter constraint cc_1 enforced; --ok
+
+create or replace view check_constraint_status as
+select conname, conrelid::regclass, conenforced, convalidated
+from pg_constraint
+where conrelid::regclass::text ~* '^parted_ch' and contype = 'c'
+order by conname, conrelid::regclass::text collate "C";
+
+alter table parted_ch alter constraint cc not enforced; --no-op
+alter table parted_ch alter constraint cc enforced; --error
+delete from parted_ch where a = 1;
+alter table parted_ch alter constraint cc enforced; --error
+delete from parted_ch where a = 9;
+alter table parted_ch alter constraint cc enforced;
+
+--check these CHECK constraint status
+select * from check_constraint_status;
+
+alter table parted_ch_2 alter constraint cc_2 enforced; --error
+delete from parted_ch where a = 16;
+alter table parted_ch_2 alter constraint cc_2 enforced;
+alter table parted_ch_2 alter constraint cc not enforced;
+alter table parted_ch_2 alter constraint cc_1 not enforced;
+alter table parted_ch_2 alter constraint cc_2 not enforced;
+
+--check these CHECK constraint status again
+select * from check_constraint_status;
+drop table parted_ch;
+drop view check_constraint_status;
+
--
-- Primary keys
--
from pg_constraint where conname like 'inh\_check\_constraint%'
order by 1, 2;
+--
+-- CHECK constraints
+-- ALTER TABLE ALTER CONSTRAINT [NOT] ENFORCED
+alter table p1 drop constraint inh_check_constraint1;
+alter table p1_c1 drop constraint inh_check_constraint1;
+
+alter table only p1 alter constraint inh_check_constraint3 enforced; --error
+alter table only p1 alter constraint inh_check_constraint3 not enforced; --error
+
+insert into p1_c1 values(-2);
+insert into p1_c3 values(-3);
+
+alter table p1 alter constraint inh_check_constraint3 enforced; --error
+delete from only p1_c1 where f1 = -2;
+alter table p1_c1 alter constraint inh_check_constraint3 enforced; --error
+
+delete from only p1_c3 where f1 = -3;
+alter table p1 alter constraint inh_check_constraint3 enforced; --ok
+alter table p1 alter constraint inh_check_constraint3 not enforced; --ok
+select conname, conenforced, convalidated, conrelid::regclass
+from pg_constraint
+where conname = 'inh_check_constraint3' and contype = 'c'
+order by conrelid::regclass::text collate "C";
+drop table p1 cascade;
+
+--for "no inherit" check constraint, it will not recurse to child table
+create table p1(f1 int constraint p1_a_check check (f1 > 0) no inherit not enforced);
+create table p1_c1(f1 int constraint p1_a_check check (f1 > 0) not enforced);
+alter table p1_c1 inherit p1;
+insert into p1_c1 values(-11);
+alter table p1 alter constraint p1_a_check enforced; --ok
+alter table p1_c1 alter constraint p1_a_check enforced; --error
drop table p1 cascade;
--
create table p1(f1 int constraint p1_a_check check (f1 > 0) not enforced);
create table p1_c1(f1 int constraint p1_a_check check (f1 > 0) enforced);
alter table p1_c1 inherit p1;
+insert into p1 values(-1); --ok
+insert into p1_c1 values(-1); --error
+alter table p1 alter constraint p1_a_check enforced; --error
+truncate p1;
+alter table p1 alter constraint p1_a_check enforced; --ok
+alter table p1 alter constraint p1_a_check not enforced; --ok
+
+select conname, conenforced, convalidated, conrelid::regclass
+from pg_constraint
+where conname = 'p1_a_check' and contype = 'c'
+order by conrelid::regclass::text collate "C";
drop table p1 cascade;
create table p1(f1 int constraint p1_a_check check (f1 > 0) enforced);
projects / thirdparty / postgresql.git / commitdiff
