From dec1949a482ae425527987a43d28c8b26ba1e0ed Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Tue, 4 Jun 2019 09:00:31 +0200 Subject: [PATCH] Add gen_random_uuid function --- doc/src/sgml/datatype.sgml | 12 ++--------- doc/src/sgml/func.sgml | 26 ++++++++++++++++++++++++ doc/src/sgml/pgcrypto.sgml | 3 ++- doc/src/sgml/uuid-ossp.sgml | 11 +++------- src/backend/utils/adt/uuid.c | 20 ++++++++++++++++++ src/include/catalog/pg_proc.dat | 3 +++ src/test/regress/expected/opr_sanity.out | 1 + src/test/regress/expected/uuid.out | 10 +++++++++ src/test/regress/sql/uuid.sql | 6 ++++++ 9 files changed, 73 insertions(+), 19 deletions(-) diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml index fc300f605f..809d98036c 100644 --- a/doc/src/sgml/datatype.sgml +++ b/doc/src/sgml/datatype.sgml @@ -4175,16 +4175,8 @@ <acronym>UUID</acronym> Type - PostgreSQL provides storage and comparison - functions for UUIDs, but the core database does not include any - function for generating UUIDs, because no single algorithm is well - suited for every application. The module - provides functions that implement several standard algorithms. - The module also provides a generation - function for random UUIDs. - Alternatively, UUIDs could be generated by client applications or - other libraries invoked through a server-side function. + See for how to generate a UUID in + PostgreSQL. diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index a79e7c0380..b6caaf6b9b 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -10291,6 +10291,32 @@ Text Search Debugging Functions + + UUID Functions + + + UUID + generating + + + + gen_random_uuid + + + + PostgreSQL includes one function to generate a UUID: + +gen_random_uuid() returns uuid + + This function returns a version 4 (random) UUID. This is the most commonly + used type of UUID and is appropriate for most applications. + + + + The module provides additional functions that + implement other standard algorithms for generating UUIDs. + + diff --git a/doc/src/sgml/pgcrypto.sgml b/doc/src/sgml/pgcrypto.sgml index 5c79666654..0acd11ed55 100644 --- a/doc/src/sgml/pgcrypto.sgml +++ b/doc/src/sgml/pgcrypto.sgml @@ -1132,7 +1132,8 @@ Random-Data Functions gen_random_uuid() returns uuid - Returns a version 4 (random) UUID. + Returns a version 4 (random) UUID. (Obsolete, this function is now also + included in core PostgreSQL.) diff --git a/doc/src/sgml/uuid-ossp.sgml b/doc/src/sgml/uuid-ossp.sgml index b3b816c372..0fbabbfda2 100644 --- a/doc/src/sgml/uuid-ossp.sgml +++ b/doc/src/sgml/uuid-ossp.sgml @@ -11,6 +11,9 @@ uuid-ossp The uuid-ossp module provides functions to generate universally unique identifiers (UUIDs) using one of several standard algorithms. There are also functions to produce certain special UUID constants. + This module is only necessary for special requirements beyond what is + available in core PostgreSQL. See for built-in ways to generate UUIDs. @@ -181,14 +184,6 @@ Building <filename>uuid-ossp</filename> More than one of these libraries might be available on a particular machine, so configure does not automatically choose one. - - - - If you only need randomly-generated (version 4) UUIDs, - consider using the gen_random_uuid() function - from the module instead. - - diff --git a/src/backend/utils/adt/uuid.c b/src/backend/utils/adt/uuid.c index 09aa6b6daa..589c2d51dd 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/pg_proc.dat b/src/include/catalog/pg_proc.dat index 87335248a0..8ecf379955 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -8341,6 +8341,9 @@ { oid => '3412', descr => 'hash', proname => 'uuid_hash_extended', prorettype => 'int8', proargtypes => 'uuid int8', prosrc => 'uuid_hash_extended' }, +{ oid => '3429', 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 85af36ee5b..33c058ff51 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 db66dc723e..090103df48 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 518d2b75c0..3bd3b357c7 100644 --- a/src/test/regress/sql/uuid.sql +++ b/src/test/regress/sql/uuid.sql @@ -75,5 +75,11 @@ CREATE UNIQUE INDEX guid1_unique_BTREE ON guid1 USING BTREE (guid_field); 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; -- 2.21.0