From 34768ee361656841a122f1c8d52a2ad753612feb Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Sun, 24 Mar 2024 07:37:13 +0100 Subject: Add temporal FOREIGN KEY contraints Add PERIOD clause to foreign key constraint definitions. This is supported for range and multirange types. Temporal foreign keys check for range containment instead of equality. This feature matches the behavior of the SQL standard temporal foreign keys, but it works on PostgreSQL's native ranges instead of SQL's "periods", which don't exist in PostgreSQL (yet). Reference actions ON {UPDATE,DELETE} {CASCADE,SET NULL,SET DEFAULT} are not supported yet. Author: Paul A. Jungwirth Reviewed-by: Peter Eisentraut Reviewed-by: jian he Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com --- src/backend/utils/adt/ruleutils.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) (limited to 'src/backend/utils/adt/ruleutils.c') diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index 4a7402e09ef..a51717e36ce 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -338,7 +338,7 @@ static char *pg_get_viewdef_worker(Oid viewoid, int prettyFlags, int wrapColumn); static char *pg_get_triggerdef_worker(Oid trigid, bool pretty); static int decompile_column_index_array(Datum column_index_array, Oid relId, - StringInfo buf); + bool withPeriod, StringInfo buf); static char *pg_get_ruledef_worker(Oid ruleoid, int prettyFlags); static char *pg_get_indexdef_worker(Oid indexrelid, int colno, const Oid *excludeOps, @@ -2253,7 +2253,8 @@ pg_get_constraintdef_worker(Oid constraintId, bool fullCommand, val = SysCacheGetAttrNotNull(CONSTROID, tup, Anum_pg_constraint_conkey); - decompile_column_index_array(val, conForm->conrelid, &buf); + /* If it is a temporal foreign key then it uses PERIOD. */ + decompile_column_index_array(val, conForm->conrelid, conForm->conperiod, &buf); /* add foreign relation name */ appendStringInfo(&buf, ") REFERENCES %s(", @@ -2264,7 +2265,7 @@ pg_get_constraintdef_worker(Oid constraintId, bool fullCommand, val = SysCacheGetAttrNotNull(CONSTROID, tup, Anum_pg_constraint_confkey); - decompile_column_index_array(val, conForm->confrelid, &buf); + decompile_column_index_array(val, conForm->confrelid, conForm->conperiod, &buf); appendStringInfoChar(&buf, ')'); @@ -2350,7 +2351,7 @@ pg_get_constraintdef_worker(Oid constraintId, bool fullCommand, if (!isnull) { appendStringInfoString(&buf, " ("); - decompile_column_index_array(val, conForm->conrelid, &buf); + decompile_column_index_array(val, conForm->conrelid, false, &buf); appendStringInfoChar(&buf, ')'); } @@ -2385,7 +2386,7 @@ pg_get_constraintdef_worker(Oid constraintId, bool fullCommand, val = SysCacheGetAttrNotNull(CONSTROID, tup, Anum_pg_constraint_conkey); - keyatts = decompile_column_index_array(val, conForm->conrelid, &buf); + keyatts = decompile_column_index_array(val, conForm->conrelid, false, &buf); if (conForm->conperiod) appendStringInfoString(&buf, " WITHOUT OVERLAPS"); @@ -2591,7 +2592,7 @@ pg_get_constraintdef_worker(Oid constraintId, bool fullCommand, */ static int decompile_column_index_array(Datum column_index_array, Oid relId, - StringInfo buf) + bool withPeriod, StringInfo buf) { Datum *keys; int nKeys; @@ -2610,7 +2611,9 @@ decompile_column_index_array(Datum column_index_array, Oid relId, if (j == 0) appendStringInfoString(buf, quote_identifier(colName)); else - appendStringInfo(buf, ", %s", quote_identifier(colName)); + appendStringInfo(buf, ", %s%s", + (withPeriod && j == nKeys - 1) ? "PERIOD " : "", + quote_identifier(colName)); } return nKeys; -- cgit v1.2.3