postgresql/src/test/regress/sql/enum.sql
Thomas Munro 212fab9926 Relax transactional restrictions on ALTER TYPE ... ADD VALUE (redux).
Originally committed as 15bc038f (plus some follow-ups), this was
reverted in 28e07270 due to a problem discovered in parallel
workers.  This new version corrects that problem by sending the
list of uncommitted enum values to parallel workers.

Here follows the original commit message describing the change:

To prevent possibly breaking indexes on enum columns, we must keep
uncommitted enum values from getting stored in tables, unless we
can be sure that any such column is new in the current transaction.

Formerly, we enforced this by disallowing ALTER TYPE ... ADD VALUE
from being executed at all in a transaction block, unless the target
enum type had been created in the current transaction.  This patch
removes that restriction, and instead insists that an uncommitted enum
value can't be referenced unless it belongs to an enum type created
in the same transaction as the value.  Per discussion, this should be
a bit less onerous.  It does require each function that could possibly
return a new enum value to SQL operations to check this restriction,
but there aren't so many of those that this seems unmaintainable.

Author: Andrew Dunstan and Tom Lane, with parallel query fix by Thomas Munro
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CAEepm%3D0Ei7g6PaNTbcmAh9tCRahQrk%3Dr5ZWLD-jr7hXweYX3yg%40mail.gmail.com
Discussion: https://postgr.es/m/4075.1459088427%40sss.pgh.pa.us
2018-10-09 12:51:01 +13:00

342 lines
9.3 KiB
PL/PgSQL

--
-- Enum tests
--
CREATE TYPE rainbow AS ENUM ('red', 'orange', 'yellow', 'green', 'blue', 'purple');
--
-- Did it create the right number of rows?
--
SELECT COUNT(*) FROM pg_enum WHERE enumtypid = 'rainbow'::regtype;
--
-- I/O functions
--
SELECT 'red'::rainbow;
SELECT 'mauve'::rainbow;
--
-- adding new values
--
CREATE TYPE planets AS ENUM ( 'venus', 'earth', 'mars' );
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
ALTER TYPE planets ADD VALUE 'uranus';
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
ALTER TYPE planets ADD VALUE 'mercury' BEFORE 'venus';
ALTER TYPE planets ADD VALUE 'saturn' BEFORE 'uranus';
ALTER TYPE planets ADD VALUE 'jupiter' AFTER 'mars';
ALTER TYPE planets ADD VALUE 'neptune' AFTER 'uranus';
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY enumlabel::planets;
-- errors for adding labels
ALTER TYPE planets ADD VALUE
'plutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutopluto';
ALTER TYPE planets ADD VALUE 'pluto' AFTER 'zeus';
-- if not exists tests
-- existing value gives error
ALTER TYPE planets ADD VALUE 'mercury';
-- unless IF NOT EXISTS is specified
ALTER TYPE planets ADD VALUE IF NOT EXISTS 'mercury';
-- should be neptune, not mercury
SELECT enum_last(NULL::planets);
ALTER TYPE planets ADD VALUE IF NOT EXISTS 'pluto';
-- should be pluto, i.e. the new value
SELECT enum_last(NULL::planets);
--
-- Test inserting so many values that we have to renumber
--
create type insenum as enum ('L1', 'L2');
alter type insenum add value 'i1' before 'L2';
alter type insenum add value 'i2' before 'L2';
alter type insenum add value 'i3' before 'L2';
alter type insenum add value 'i4' before 'L2';
alter type insenum add value 'i5' before 'L2';
alter type insenum add value 'i6' before 'L2';
alter type insenum add value 'i7' before 'L2';
alter type insenum add value 'i8' before 'L2';
alter type insenum add value 'i9' before 'L2';
alter type insenum add value 'i10' before 'L2';
alter type insenum add value 'i11' before 'L2';
alter type insenum add value 'i12' before 'L2';
alter type insenum add value 'i13' before 'L2';
alter type insenum add value 'i14' before 'L2';
alter type insenum add value 'i15' before 'L2';
alter type insenum add value 'i16' before 'L2';
alter type insenum add value 'i17' before 'L2';
alter type insenum add value 'i18' before 'L2';
alter type insenum add value 'i19' before 'L2';
alter type insenum add value 'i20' before 'L2';
alter type insenum add value 'i21' before 'L2';
alter type insenum add value 'i22' before 'L2';
alter type insenum add value 'i23' before 'L2';
alter type insenum add value 'i24' before 'L2';
alter type insenum add value 'i25' before 'L2';
alter type insenum add value 'i26' before 'L2';
alter type insenum add value 'i27' before 'L2';
alter type insenum add value 'i28' before 'L2';
alter type insenum add value 'i29' before 'L2';
alter type insenum add value 'i30' before 'L2';
-- The exact values of enumsortorder will now depend on the local properties
-- of float4, but in any reasonable implementation we should get at least
-- 20 splits before having to renumber; so only hide values > 20.
SELECT enumlabel,
case when enumsortorder > 20 then null else enumsortorder end as so
FROM pg_enum
WHERE enumtypid = 'insenum'::regtype
ORDER BY enumsortorder;
--
-- Basic table creation, row selection
--
CREATE TABLE enumtest (col rainbow);
INSERT INTO enumtest values ('red'), ('orange'), ('yellow'), ('green');
COPY enumtest FROM stdin;
blue
purple
\.
SELECT * FROM enumtest;
--
-- Operators, no index
--
SELECT * FROM enumtest WHERE col = 'orange';
SELECT * FROM enumtest WHERE col <> 'orange' ORDER BY col;
SELECT * FROM enumtest WHERE col > 'yellow' ORDER BY col;
SELECT * FROM enumtest WHERE col >= 'yellow' ORDER BY col;
SELECT * FROM enumtest WHERE col < 'green' ORDER BY col;
SELECT * FROM enumtest WHERE col <= 'green' ORDER BY col;
--
-- Cast to/from text
--
SELECT 'red'::rainbow::text || 'hithere';
SELECT 'red'::text::rainbow = 'red'::rainbow;
--
-- Aggregates
--
SELECT min(col) FROM enumtest;
SELECT max(col) FROM enumtest;
SELECT max(col) FROM enumtest WHERE col < 'green';
--
-- Index tests, force use of index
--
SET enable_seqscan = off;
SET enable_bitmapscan = off;
--
-- Btree index / opclass with the various operators
--
CREATE UNIQUE INDEX enumtest_btree ON enumtest USING btree (col);
SELECT * FROM enumtest WHERE col = 'orange';
SELECT * FROM enumtest WHERE col <> 'orange' ORDER BY col;
SELECT * FROM enumtest WHERE col > 'yellow' ORDER BY col;
SELECT * FROM enumtest WHERE col >= 'yellow' ORDER BY col;
SELECT * FROM enumtest WHERE col < 'green' ORDER BY col;
SELECT * FROM enumtest WHERE col <= 'green' ORDER BY col;
SELECT min(col) FROM enumtest;
SELECT max(col) FROM enumtest;
SELECT max(col) FROM enumtest WHERE col < 'green';
DROP INDEX enumtest_btree;
--
-- Hash index / opclass with the = operator
--
CREATE INDEX enumtest_hash ON enumtest USING hash (col);
SELECT * FROM enumtest WHERE col = 'orange';
DROP INDEX enumtest_hash;
--
-- End index tests
--
RESET enable_seqscan;
RESET enable_bitmapscan;
--
-- Domains over enums
--
CREATE DOMAIN rgb AS rainbow CHECK (VALUE IN ('red', 'green', 'blue'));
SELECT 'red'::rgb;
SELECT 'purple'::rgb;
SELECT 'purple'::rainbow::rgb;
DROP DOMAIN rgb;
--
-- Arrays
--
SELECT '{red,green,blue}'::rainbow[];
SELECT ('{red,green,blue}'::rainbow[])[2];
SELECT 'red' = ANY ('{red,green,blue}'::rainbow[]);
SELECT 'yellow' = ANY ('{red,green,blue}'::rainbow[]);
SELECT 'red' = ALL ('{red,green,blue}'::rainbow[]);
SELECT 'red' = ALL ('{red,red}'::rainbow[]);
--
-- Support functions
--
SELECT enum_first(NULL::rainbow);
SELECT enum_last('green'::rainbow);
SELECT enum_range(NULL::rainbow);
SELECT enum_range('orange'::rainbow, 'green'::rainbow);
SELECT enum_range(NULL, 'green'::rainbow);
SELECT enum_range('orange'::rainbow, NULL);
SELECT enum_range(NULL::rainbow, NULL);
--
-- User functions, can't test perl/python etc here since may not be compiled.
--
CREATE FUNCTION echo_me(anyenum) RETURNS text AS $$
BEGIN
RETURN $1::text || 'omg';
END
$$ LANGUAGE plpgsql;
SELECT echo_me('red'::rainbow);
--
-- Concrete function should override generic one
--
CREATE FUNCTION echo_me(rainbow) RETURNS text AS $$
BEGIN
RETURN $1::text || 'wtf';
END
$$ LANGUAGE plpgsql;
SELECT echo_me('red'::rainbow);
--
-- If we drop the original generic one, we don't have to qualify the type
-- anymore, since there's only one match
--
DROP FUNCTION echo_me(anyenum);
SELECT echo_me('red');
DROP FUNCTION echo_me(rainbow);
--
-- RI triggers on enum types
--
CREATE TABLE enumtest_parent (id rainbow PRIMARY KEY);
CREATE TABLE enumtest_child (parent rainbow REFERENCES enumtest_parent);
INSERT INTO enumtest_parent VALUES ('red');
INSERT INTO enumtest_child VALUES ('red');
INSERT INTO enumtest_child VALUES ('blue'); -- fail
DELETE FROM enumtest_parent; -- fail
--
-- cross-type RI should fail
--
CREATE TYPE bogus AS ENUM('good', 'bad', 'ugly');
CREATE TABLE enumtest_bogus_child(parent bogus REFERENCES enumtest_parent);
DROP TYPE bogus;
-- check renaming a value
ALTER TYPE rainbow RENAME VALUE 'red' TO 'crimson';
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'rainbow'::regtype
ORDER BY 2;
-- check that renaming a non-existent value fails
ALTER TYPE rainbow RENAME VALUE 'red' TO 'crimson';
-- check that renaming to an existent value fails
ALTER TYPE rainbow RENAME VALUE 'blue' TO 'green';
--
-- check transactional behaviour of ALTER TYPE ... ADD VALUE
--
CREATE TYPE bogus AS ENUM('good');
-- check that we can add new values to existing enums in a transaction
-- but we can't use them
BEGIN;
ALTER TYPE bogus ADD VALUE 'new';
SAVEPOINT x;
SELECT 'new'::bogus; -- unsafe
ROLLBACK TO x;
SELECT enum_first(null::bogus); -- safe
SELECT enum_last(null::bogus); -- unsafe
ROLLBACK TO x;
SELECT enum_range(null::bogus); -- unsafe
ROLLBACK TO x;
COMMIT;
SELECT 'new'::bogus; -- now safe
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'bogus'::regtype
ORDER BY 2;
-- check that we recognize the case where the enum already existed but was
-- modified in the current txn; this should not be considered safe
BEGIN;
ALTER TYPE bogus RENAME TO bogon;
ALTER TYPE bogon ADD VALUE 'bad';
SELECT 'bad'::bogon;
ROLLBACK;
-- but a renamed value is safe to use later in same transaction
BEGIN;
ALTER TYPE bogus RENAME VALUE 'good' to 'bad';
SELECT 'bad'::bogus;
ROLLBACK;
DROP TYPE bogus;
-- check that values created during CREATE TYPE can be used in any case
BEGIN;
CREATE TYPE bogus AS ENUM('good','bad','ugly');
ALTER TYPE bogus RENAME TO bogon;
select enum_range(null::bogon);
ROLLBACK;
-- ideally, we'd allow this usage; but it requires keeping track of whether
-- the enum type was created in the current transaction, which is expensive
BEGIN;
CREATE TYPE bogus AS ENUM('good');
ALTER TYPE bogus RENAME TO bogon;
ALTER TYPE bogon ADD VALUE 'bad';
ALTER TYPE bogon ADD VALUE 'ugly';
select enum_range(null::bogon); -- fails
ROLLBACK;
--
-- Cleanup
--
DROP TABLE enumtest_child;
DROP TABLE enumtest_parent;
DROP TABLE enumtest;
DROP TYPE rainbow;
--
-- Verify properly cleaned up
--
SELECT COUNT(*) FROM pg_type WHERE typname = 'rainbow';
SELECT * FROM pg_enum WHERE NOT EXISTS
(SELECT 1 FROM pg_type WHERE pg_type.oid = enumtypid);