6 files changed, 41 insertions, 1 deletions
diff --git a/src/backend/utils/adt/uuid.c b/src/backend/utils/adt/uuid.c
index 09aa6b6daab..589c2d51dde 100644
--- a/src/backend/utils/adt/uuid.c
+++ b/src/backend/utils/adt/uuid.c
@@ -416,3 +416,23 @@ uuid_hash_extended(PG_FUNCTION_ARGS)
 
 	return hash_any_extended(key->data, UUID_LEN, PG_GETARG_INT64(1));
 }
+
+Datum
+gen_random_uuid(PG_FUNCTION_ARGS)
+{
+	pg_uuid_t  *uuid = palloc(UUID_LEN);
+
+	if (!pg_strong_random(uuid, UUID_LEN))
+		ereport(ERROR,
+				(errcode(ERRCODE_INTERNAL_ERROR),
+				 errmsg("could not generate random values")));
+
+	/*
+	 * Set magic numbers for a "version 4" (pseudorandom) UUID, see
+	 * http://tools.ietf.org/html/rfc4122#section-4.4
+	 */
+	uuid->data[6] = (uuid->data[6] & 0x0f) | 0x40;	/* time_hi_and_version */
+	uuid->data[8] = (uuid->data[8] & 0x3f) | 0x80;	/* clock_seq_hi_and_reserved */
+
+	PG_RETURN_UUID_P(uuid);
+}
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index e3a6e8dc410..19ccb54796b 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	201907141
+#define CATALOG_VERSION_NO	201907142
 
 #endif
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 762c099e516..0902dce5f14 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -8376,6 +8376,9 @@
 { oid => '3412', descr => 'hash',
   proname => 'uuid_hash_extended', prorettype => 'int8',
   proargtypes => 'uuid int8', prosrc => 'uuid_hash_extended' },
+{ oid => '3432', descr => 'generate random UUID',
+  proname => 'gen_random_uuid', proleakproof => 't', prorettype => 'uuid',
+  proargtypes => '', prosrc => 'gen_random_uuid' },
 
 # pg_lsn
 { oid => '3229', descr => 'I/O',
diff --git a/src/test/regress/expected/opr_sanity.out b/src/test/regress/expected/opr_sanity.out
index 85af36ee5bc..33c058ff514 100644
--- a/src/test/regress/expected/opr_sanity.out
+++ b/src/test/regress/expected/opr_sanity.out
@@ -742,6 +742,7 @@ sha224(bytea)
 sha256(bytea)
 sha384(bytea)
 sha512(bytea)
+gen_random_uuid()
 starts_with(text,text)
 macaddr8_eq(macaddr8,macaddr8)
 macaddr8_lt(macaddr8,macaddr8)
diff --git a/src/test/regress/expected/uuid.out b/src/test/regress/expected/uuid.out
index db66dc723ef..090103df48a 100644
--- a/src/test/regress/expected/uuid.out
+++ b/src/test/regress/expected/uuid.out
@@ -145,5 +145,15 @@ SELECT COUNT(*) FROM guid1 g1 LEFT JOIN guid2 g2 ON g1.guid_field = g2.guid_fiel
      1
 (1 row)
 
+-- generation test
+TRUNCATE guid1;
+INSERT INTO guid1 (guid_field) VALUES (gen_random_uuid());
+INSERT INTO guid1 (guid_field) VALUES (gen_random_uuid());
+SELECT count(DISTINCT guid_field) FROM guid1;
+ count 
+-------
+     2
+(1 row)
+
 -- clean up
 DROP TABLE guid1, guid2 CASCADE;
diff --git a/src/test/regress/sql/uuid.sql b/src/test/regress/sql/uuid.sql
index 518d2b75c00..3bd3b357c77 100644
--- a/src/test/regress/sql/uuid.sql
+++ b/src/test/regress/sql/uuid.sql
@@ -75,5 +75,11 @@ INSERT INTO guid2(guid_field) VALUES('3f3e3c3b3a3039383736353433a2313e');
 SELECT COUNT(*) FROM guid1 g1 INNER JOIN guid2 g2 ON g1.guid_field = g2.guid_field;
 SELECT COUNT(*) FROM guid1 g1 LEFT JOIN guid2 g2 ON g1.guid_field = g2.guid_field WHERE g2.guid_field IS NULL;
 
+-- generation test
+TRUNCATE guid1;
+INSERT INTO guid1 (guid_field) VALUES (gen_random_uuid());
+INSERT INTO guid1 (guid_field) VALUES (gen_random_uuid());
+SELECT count(DISTINCT guid_field) FROM guid1;
+
 -- clean up
 DROP TABLE guid1, guid2 CASCADE;