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Fast ALTER TABLE ADD COLUMN with a non-NULL default
Currently adding a column to a table with a non-NULL default results in a rewrite of the table. For large tables this can be both expensive and disruptive. This patch removes the need for the rewrite as long as the default value is not volatile. The default expression is evaluated at the time of the ALTER TABLE and the result stored in a new column (attmissingval) in pg_attribute, and a new column (atthasmissing) is set to true. Any existing row when fetched will be supplied with the attmissingval. New rows will have the supplied value or the default and so will never need the attmissingval. Any time the table is rewritten all the atthasmissing and attmissingval settings for the attributes are cleared, as they are no longer needed. The most visible code change from this is in heap_attisnull, which acquires a third TupleDesc argument, allowing it to detect a missing value if there is one. In many cases where it is known that there will not be any (e.g. catalog relations) NULL can be passed for this argument. Andrew Dunstan, heavily modified from an original patch from Serge Rielau. Reviewed by Tom Lane, Andres Freund, Tomas Vondra and David Rowley. Discussion: https://postgr.es/m/31e2e921-7002-4c27-59f5-51f08404c858@2ndQuadrant.com
This commit is contained in:
Andrew Dunstan
@ -389,8 +389,6 @@ alter table rewriteme alter column foo type numeric;
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ERROR: rewrites not allowed
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CONTEXT: PL/pgSQL function test_evtrig_no_rewrite() line 3 at RAISE
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alter table rewriteme add column baz int default 0;
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ERROR: rewrites not allowed
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CONTEXT: PL/pgSQL function test_evtrig_no_rewrite() line 3 at RAISE
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-- test with more than one reason to rewrite a single table
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CREATE OR REPLACE FUNCTION test_evtrig_no_rewrite() RETURNS event_trigger
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LANGUAGE plpgsql AS $$
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@ -404,7 +402,7 @@ alter table rewriteme
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add column onemore int default 0,
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add column another int default -1,
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alter column foo type numeric(10,4);
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NOTICE: Table 'rewriteme' is being rewritten (reason = 6)
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NOTICE: Table 'rewriteme' is being rewritten (reason = 4)
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-- shouldn't trigger a table_rewrite event
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alter table rewriteme alter column foo type numeric(12,4);
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-- typed tables are rewritten when their type changes. Don't emit table
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515
src/test/regress/expected/fast_default.out
Normal file
515
src/test/regress/expected/fast_default.out
Normal file
@ -0,0 +1,515 @@
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--
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-- ALTER TABLE ADD COLUMN DEFAULT test
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--
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SET search_path = fast_default;
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CREATE SCHEMA fast_default;
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CREATE TABLE m(id OID);
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INSERT INTO m VALUES (NULL::OID);
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CREATE FUNCTION set(tabname name) RETURNS VOID
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AS $$
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BEGIN
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UPDATE m
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SET id = (SELECT c.relfilenode
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FROM pg_class AS c, pg_namespace AS s
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WHERE c.relname = tabname
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AND c.relnamespace = s.oid
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AND s.nspname = 'fast_default');
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END;
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$$ LANGUAGE 'plpgsql';
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CREATE FUNCTION comp() RETURNS TEXT
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AS $$
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BEGIN
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RETURN (SELECT CASE
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WHEN m.id = c.relfilenode THEN 'Unchanged'
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ELSE 'Rewritten'
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END
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FROM m, pg_class AS c, pg_namespace AS s
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WHERE c.relname = 't'
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AND c.relnamespace = s.oid
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AND s.nspname = 'fast_default');
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END;
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$$ LANGUAGE 'plpgsql';
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CREATE FUNCTION log_rewrite() RETURNS event_trigger
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LANGUAGE plpgsql as
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$func$
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declare
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this_schema text;
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begin
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select into this_schema relnamespace::regnamespace::text
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from pg_class
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where oid = pg_event_trigger_table_rewrite_oid();
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if this_schema = 'fast_default'
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then
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RAISE NOTICE 'rewriting table % for reason %',
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pg_event_trigger_table_rewrite_oid()::regclass,
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pg_event_trigger_table_rewrite_reason();
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end if;
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end;
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$func$;
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CREATE TABLE has_volatile AS
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SELECT * FROM generate_series(1,10) id;
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CREATE EVENT TRIGGER has_volatile_rewrite
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ON table_rewrite
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EXECUTE PROCEDURE log_rewrite();
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-- only the last of these should trigger a rewrite
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ALTER TABLE has_volatile ADD col1 int;
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ALTER TABLE has_volatile ADD col2 int DEFAULT 1;
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ALTER TABLE has_volatile ADD col3 timestamptz DEFAULT current_timestamp;
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ALTER TABLE has_volatile ADD col4 int DEFAULT (random() * 10000)::int;
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NOTICE: rewriting table has_volatile for reason 2
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-- Test a large sample of different datatypes
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CREATE TABLE T(pk INT NOT NULL PRIMARY KEY, c_int INT DEFAULT 1);
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SELECT set('t');
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set
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-----
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(1 row)
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INSERT INTO T VALUES (1), (2);
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ALTER TABLE T ADD COLUMN c_bpchar BPCHAR(5) DEFAULT 'hello',
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ALTER COLUMN c_int SET DEFAULT 2;
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INSERT INTO T VALUES (3), (4);
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ALTER TABLE T ADD COLUMN c_text TEXT DEFAULT 'world',
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ALTER COLUMN c_bpchar SET DEFAULT 'dog';
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INSERT INTO T VALUES (5), (6);
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ALTER TABLE T ADD COLUMN c_date DATE DEFAULT '2016-06-02',
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ALTER COLUMN c_text SET DEFAULT 'cat';
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INSERT INTO T VALUES (7), (8);
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ALTER TABLE T ADD COLUMN c_timestamp TIMESTAMP DEFAULT '2016-09-01 12:00:00',
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ADD COLUMN c_timestamp_null TIMESTAMP,
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ALTER COLUMN c_date SET DEFAULT '2010-01-01';
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INSERT INTO T VALUES (9), (10);
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ALTER TABLE T ADD COLUMN c_array TEXT[]
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DEFAULT '{"This", "is", "the", "real", "world"}',
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ALTER COLUMN c_timestamp SET DEFAULT '1970-12-31 11:12:13',
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ALTER COLUMN c_timestamp_null SET DEFAULT '2016-09-29 12:00:00';
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INSERT INTO T VALUES (11), (12);
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ALTER TABLE T ADD COLUMN c_small SMALLINT DEFAULT -5,
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ADD COLUMN c_small_null SMALLINT,
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ALTER COLUMN c_array
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SET DEFAULT '{"This", "is", "no", "fantasy"}';
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INSERT INTO T VALUES (13), (14);
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ALTER TABLE T ADD COLUMN c_big BIGINT DEFAULT 180000000000018,
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ALTER COLUMN c_small SET DEFAULT 9,
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ALTER COLUMN c_small_null SET DEFAULT 13;
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INSERT INTO T VALUES (15), (16);
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ALTER TABLE T ADD COLUMN c_num NUMERIC DEFAULT 1.00000000001,
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ALTER COLUMN c_big SET DEFAULT -9999999999999999;
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INSERT INTO T VALUES (17), (18);
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ALTER TABLE T ADD COLUMN c_time TIME DEFAULT '12:00:00',
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ALTER COLUMN c_num SET DEFAULT 2.000000000000002;
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INSERT INTO T VALUES (19), (20);
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ALTER TABLE T ADD COLUMN c_interval INTERVAL DEFAULT '1 day',
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ALTER COLUMN c_time SET DEFAULT '23:59:59';
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INSERT INTO T VALUES (21), (22);
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ALTER TABLE T ADD COLUMN c_hugetext TEXT DEFAULT repeat('abcdefg',1000),
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ALTER COLUMN c_interval SET DEFAULT '3 hours';
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INSERT INTO T VALUES (23), (24);
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ALTER TABLE T ALTER COLUMN c_interval DROP DEFAULT,
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ALTER COLUMN c_hugetext SET DEFAULT repeat('poiuyt', 1000);
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INSERT INTO T VALUES (25), (26);
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ALTER TABLE T ALTER COLUMN c_bpchar DROP DEFAULT,
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ALTER COLUMN c_date DROP DEFAULT,
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ALTER COLUMN c_text DROP DEFAULT,
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ALTER COLUMN c_timestamp DROP DEFAULT,
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ALTER COLUMN c_array DROP DEFAULT,
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ALTER COLUMN c_small DROP DEFAULT,
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ALTER COLUMN c_big DROP DEFAULT,
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ALTER COLUMN c_num DROP DEFAULT,
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ALTER COLUMN c_time DROP DEFAULT,
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ALTER COLUMN c_hugetext DROP DEFAULT;
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INSERT INTO T VALUES (27), (28);
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SELECT pk, c_int, c_bpchar, c_text, c_date, c_timestamp,
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c_timestamp_null, c_array, c_small, c_small_null,
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c_big, c_num, c_time, c_interval,
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c_hugetext = repeat('abcdefg',1000) as c_hugetext_origdef,
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c_hugetext = repeat('poiuyt', 1000) as c_hugetext_newdef
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FROM T ORDER BY pk;
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pk | c_int | c_bpchar | c_text | c_date | c_timestamp | c_timestamp_null | c_array | c_small | c_small_null | c_big | c_num | c_time | c_interval | c_hugetext_origdef | c_hugetext_newdef
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----+-------+----------+--------+------------+--------------------------+--------------------------+--------------------------+---------+--------------+-------------------+-------------------+----------+------------+--------------------+-------------------
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1 | 1 | hello | world | 06-02-2016 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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2 | 1 | hello | world | 06-02-2016 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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3 | 2 | hello | world | 06-02-2016 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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4 | 2 | hello | world | 06-02-2016 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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5 | 2 | dog | world | 06-02-2016 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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6 | 2 | dog | world | 06-02-2016 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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7 | 2 | dog | cat | 06-02-2016 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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8 | 2 | dog | cat | 06-02-2016 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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9 | 2 | dog | cat | 01-01-2010 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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10 | 2 | dog | cat | 01-01-2010 | Thu Sep 01 12:00:00 2016 | | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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11 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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12 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,the,real,world} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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13 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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14 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | -5 | | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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15 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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16 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | 180000000000018 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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17 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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18 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 1.00000000001 | 12:00:00 | @ 1 day | t | f
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19 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 2.000000000000002 | 12:00:00 | @ 1 day | t | f
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20 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 2.000000000000002 | 12:00:00 | @ 1 day | t | f
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21 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 2.000000000000002 | 23:59:59 | @ 1 day | t | f
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22 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 2.000000000000002 | 23:59:59 | @ 1 day | t | f
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23 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 2.000000000000002 | 23:59:59 | @ 3 hours | t | f
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24 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 2.000000000000002 | 23:59:59 | @ 3 hours | t | f
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25 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 2.000000000000002 | 23:59:59 | | f | t
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26 | 2 | dog | cat | 01-01-2010 | Thu Dec 31 11:12:13 1970 | Thu Sep 29 12:00:00 2016 | {This,is,no,fantasy} | 9 | 13 | -9999999999999999 | 2.000000000000002 | 23:59:59 | | f | t
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27 | 2 | | | | | Thu Sep 29 12:00:00 2016 | | | 13 | | | | | |
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28 | 2 | | | | | Thu Sep 29 12:00:00 2016 | | | 13 | | | | | |
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(28 rows)
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SELECT comp();
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comp
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-----------
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Unchanged
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(1 row)
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DROP TABLE T;
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-- Test expressions in the defaults
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CREATE OR REPLACE FUNCTION foo(a INT) RETURNS TEXT AS $$
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DECLARE res TEXT := '';
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i INT;
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BEGIN
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i := 0;
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WHILE (i < a) LOOP
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res := res || chr(ascii('a') + i);
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i := i + 1;
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END LOOP;
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RETURN res;
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END; $$ LANGUAGE PLPGSQL STABLE;
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CREATE TABLE T(pk INT NOT NULL PRIMARY KEY, c_int INT DEFAULT LENGTH(foo(6)));
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SELECT set('t');
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set
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-----
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(1 row)
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INSERT INTO T VALUES (1), (2);
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ALTER TABLE T ADD COLUMN c_bpchar BPCHAR(5) DEFAULT foo(4),
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ALTER COLUMN c_int SET DEFAULT LENGTH(foo(8));
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INSERT INTO T VALUES (3), (4);
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ALTER TABLE T ADD COLUMN c_text TEXT DEFAULT foo(6),
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ALTER COLUMN c_bpchar SET DEFAULT foo(3);
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INSERT INTO T VALUES (5), (6);
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ALTER TABLE T ADD COLUMN c_date DATE
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DEFAULT '2016-06-02'::DATE + LENGTH(foo(10)),
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ALTER COLUMN c_text SET DEFAULT foo(12);
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INSERT INTO T VALUES (7), (8);
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ALTER TABLE T ADD COLUMN c_timestamp TIMESTAMP
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DEFAULT '2016-09-01'::DATE + LENGTH(foo(10)),
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ALTER COLUMN c_date
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SET DEFAULT '2010-01-01'::DATE - LENGTH(foo(4));
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INSERT INTO T VALUES (9), (10);
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ALTER TABLE T ADD COLUMN c_array TEXT[]
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DEFAULT ('{"This", "is", "' || foo(4) ||
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'","the", "real", "world"}')::TEXT[],
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ALTER COLUMN c_timestamp
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SET DEFAULT '1970-12-31'::DATE + LENGTH(foo(30));
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INSERT INTO T VALUES (11), (12);
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ALTER TABLE T ALTER COLUMN c_int DROP DEFAULT,
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ALTER COLUMN c_array
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SET DEFAULT ('{"This", "is", "' || foo(1) ||
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'", "fantasy"}')::text[];
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INSERT INTO T VALUES (13), (14);
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ALTER TABLE T ALTER COLUMN c_bpchar DROP DEFAULT,
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ALTER COLUMN c_date DROP DEFAULT,
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ALTER COLUMN c_text DROP DEFAULT,
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ALTER COLUMN c_timestamp DROP DEFAULT,
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ALTER COLUMN c_array DROP DEFAULT;
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INSERT INTO T VALUES (15), (16);
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SELECT * FROM T;
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pk | c_int | c_bpchar | c_text | c_date | c_timestamp | c_array
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----+-------+----------+--------------+------------+--------------------------+-------------------------------
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1 | 6 | abcd | abcdef | 06-12-2016 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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2 | 6 | abcd | abcdef | 06-12-2016 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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3 | 8 | abcd | abcdef | 06-12-2016 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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4 | 8 | abcd | abcdef | 06-12-2016 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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5 | 8 | abc | abcdef | 06-12-2016 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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6 | 8 | abc | abcdef | 06-12-2016 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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7 | 8 | abc | abcdefghijkl | 06-12-2016 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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8 | 8 | abc | abcdefghijkl | 06-12-2016 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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9 | 8 | abc | abcdefghijkl | 12-28-2009 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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10 | 8 | abc | abcdefghijkl | 12-28-2009 | Sun Sep 11 00:00:00 2016 | {This,is,abcd,the,real,world}
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11 | 8 | abc | abcdefghijkl | 12-28-2009 | Sat Jan 30 00:00:00 1971 | {This,is,abcd,the,real,world}
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12 | 8 | abc | abcdefghijkl | 12-28-2009 | Sat Jan 30 00:00:00 1971 | {This,is,abcd,the,real,world}
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13 | | abc | abcdefghijkl | 12-28-2009 | Sat Jan 30 00:00:00 1971 | {This,is,a,fantasy}
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14 | | abc | abcdefghijkl | 12-28-2009 | Sat Jan 30 00:00:00 1971 | {This,is,a,fantasy}
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15 | | | | | |
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16 | | | | | |
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(16 rows)
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SELECT comp();
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comp
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-----------
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Unchanged
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(1 row)
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DROP TABLE T;
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DROP FUNCTION foo(INT);
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-- Fall back to full rewrite for volatile expressions
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CREATE TABLE T(pk INT NOT NULL PRIMARY KEY);
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INSERT INTO T VALUES (1);
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SELECT set('t');
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set
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-----
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(1 row)
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-- now() is stable, because it returns the transaction timestamp
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ALTER TABLE T ADD COLUMN c1 TIMESTAMP DEFAULT now();
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SELECT comp();
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comp
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-----------
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Unchanged
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(1 row)
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-- clock_timestamp() is volatile
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ALTER TABLE T ADD COLUMN c2 TIMESTAMP DEFAULT clock_timestamp();
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NOTICE: rewriting table t for reason 2
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SELECT comp();
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comp
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-----------
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Rewritten
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(1 row)
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DROP TABLE T;
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-- Simple querie
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CREATE TABLE T (pk INT NOT NULL PRIMARY KEY);
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SELECT set('t');
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set
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-----
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|
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(1 row)
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INSERT INTO T SELECT * FROM generate_series(1, 10) a;
|
||||
ALTER TABLE T ADD COLUMN c_bigint BIGINT NOT NULL DEFAULT -1;
|
||||
INSERT INTO T SELECT b, b - 10 FROM generate_series(11, 20) a(b);
|
||||
ALTER TABLE T ADD COLUMN c_text TEXT DEFAULT 'hello';
|
||||
INSERT INTO T SELECT b, b - 10, (b + 10)::text FROM generate_series(21, 30) a(b);
|
||||
-- WHERE clause
|
||||
SELECT c_bigint, c_text FROM T WHERE c_bigint = -1 LIMIT 1;
|
||||
c_bigint | c_text
|
||||
----------+--------
|
||||
-1 | hello
|
||||
(1 row)
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE)
|
||||
SELECT c_bigint, c_text FROM T WHERE c_bigint = -1 LIMIT 1;
|
||||
QUERY PLAN
|
||||
----------------------------------------------
|
||||
Limit
|
||||
Output: c_bigint, c_text
|
||||
-> Seq Scan on fast_default.t
|
||||
Output: c_bigint, c_text
|
||||
Filter: (t.c_bigint = '-1'::integer)
|
||||
(5 rows)
|
||||
|
||||
SELECT c_bigint, c_text FROM T WHERE c_text = 'hello' LIMIT 1;
|
||||
c_bigint | c_text
|
||||
----------+--------
|
||||
-1 | hello
|
||||
(1 row)
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE) SELECT c_bigint, c_text FROM T WHERE c_text = 'hello' LIMIT 1;
|
||||
QUERY PLAN
|
||||
--------------------------------------------
|
||||
Limit
|
||||
Output: c_bigint, c_text
|
||||
-> Seq Scan on fast_default.t
|
||||
Output: c_bigint, c_text
|
||||
Filter: (t.c_text = 'hello'::text)
|
||||
(5 rows)
|
||||
|
||||
-- COALESCE
|
||||
SELECT COALESCE(c_bigint, pk), COALESCE(c_text, pk::text)
|
||||
FROM T
|
||||
ORDER BY pk LIMIT 10;
|
||||
coalesce | coalesce
|
||||
----------+----------
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
-1 | hello
|
||||
(10 rows)
|
||||
|
||||
-- Aggregate function
|
||||
SELECT SUM(c_bigint), MAX(c_text), MIN(c_text) FROM T;
|
||||
sum | max | min
|
||||
-----+-------+-----
|
||||
200 | hello | 31
|
||||
(1 row)
|
||||
|
||||
-- ORDER BY
|
||||
SELECT * FROM T ORDER BY c_bigint, c_text, pk LIMIT 10;
|
||||
pk | c_bigint | c_text
|
||||
----+----------+--------
|
||||
1 | -1 | hello
|
||||
2 | -1 | hello
|
||||
3 | -1 | hello
|
||||
4 | -1 | hello
|
||||
5 | -1 | hello
|
||||
6 | -1 | hello
|
||||
7 | -1 | hello
|
||||
8 | -1 | hello
|
||||
9 | -1 | hello
|
||||
10 | -1 | hello
|
||||
(10 rows)
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE)
|
||||
SELECT * FROM T ORDER BY c_bigint, c_text, pk LIMIT 10;
|
||||
QUERY PLAN
|
||||
----------------------------------------------
|
||||
Limit
|
||||
Output: pk, c_bigint, c_text
|
||||
-> Sort
|
||||
Output: pk, c_bigint, c_text
|
||||
Sort Key: t.c_bigint, t.c_text, t.pk
|
||||
-> Seq Scan on fast_default.t
|
||||
Output: pk, c_bigint, c_text
|
||||
(7 rows)
|
||||
|
||||
-- LIMIT
|
||||
SELECT * FROM T WHERE c_bigint > -1 ORDER BY c_bigint, c_text, pk LIMIT 10;
|
||||
pk | c_bigint | c_text
|
||||
----+----------+--------
|
||||
11 | 1 | hello
|
||||
12 | 2 | hello
|
||||
13 | 3 | hello
|
||||
14 | 4 | hello
|
||||
15 | 5 | hello
|
||||
16 | 6 | hello
|
||||
17 | 7 | hello
|
||||
18 | 8 | hello
|
||||
19 | 9 | hello
|
||||
20 | 10 | hello
|
||||
(10 rows)
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE)
|
||||
SELECT * FROM T WHERE c_bigint > -1 ORDER BY c_bigint, c_text, pk LIMIT 10;
|
||||
QUERY PLAN
|
||||
----------------------------------------------------
|
||||
Limit
|
||||
Output: pk, c_bigint, c_text
|
||||
-> Sort
|
||||
Output: pk, c_bigint, c_text
|
||||
Sort Key: t.c_bigint, t.c_text, t.pk
|
||||
-> Seq Scan on fast_default.t
|
||||
Output: pk, c_bigint, c_text
|
||||
Filter: (t.c_bigint > '-1'::integer)
|
||||
(8 rows)
|
||||
|
||||
-- DELETE with RETURNING
|
||||
DELETE FROM T WHERE pk BETWEEN 10 AND 20 RETURNING *;
|
||||
pk | c_bigint | c_text
|
||||
----+----------+--------
|
||||
10 | -1 | hello
|
||||
11 | 1 | hello
|
||||
12 | 2 | hello
|
||||
13 | 3 | hello
|
||||
14 | 4 | hello
|
||||
15 | 5 | hello
|
||||
16 | 6 | hello
|
||||
17 | 7 | hello
|
||||
18 | 8 | hello
|
||||
19 | 9 | hello
|
||||
20 | 10 | hello
|
||||
(11 rows)
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE)
|
||||
DELETE FROM T WHERE pk BETWEEN 10 AND 20 RETURNING *;
|
||||
QUERY PLAN
|
||||
-----------------------------------------------------------
|
||||
Delete on fast_default.t
|
||||
Output: pk, c_bigint, c_text
|
||||
-> Bitmap Heap Scan on fast_default.t
|
||||
Output: ctid
|
||||
Recheck Cond: ((t.pk >= 10) AND (t.pk <= 20))
|
||||
-> Bitmap Index Scan on t_pkey
|
||||
Index Cond: ((t.pk >= 10) AND (t.pk <= 20))
|
||||
(7 rows)
|
||||
|
||||
-- UPDATE
|
||||
UPDATE T SET c_text = '"' || c_text || '"' WHERE pk < 10;
|
||||
SELECT * FROM T WHERE c_text LIKE '"%"' ORDER BY PK;
|
||||
pk | c_bigint | c_text
|
||||
----+----------+---------
|
||||
1 | -1 | "hello"
|
||||
2 | -1 | "hello"
|
||||
3 | -1 | "hello"
|
||||
4 | -1 | "hello"
|
||||
5 | -1 | "hello"
|
||||
6 | -1 | "hello"
|
||||
7 | -1 | "hello"
|
||||
8 | -1 | "hello"
|
||||
9 | -1 | "hello"
|
||||
(9 rows)
|
||||
|
||||
SELECT comp();
|
||||
comp
|
||||
-----------
|
||||
Unchanged
|
||||
(1 row)
|
||||
|
||||
DROP TABLE T;
|
||||
-- Combine with other DDL
|
||||
CREATE TABLE T(pk INT NOT NULL PRIMARY KEY);
|
||||
SELECT set('t');
|
||||
set
|
||||
-----
|
||||
|
||||
(1 row)
|
||||
|
||||
INSERT INTO T VALUES (1), (2);
|
||||
ALTER TABLE T ADD COLUMN c_int INT NOT NULL DEFAULT -1;
|
||||
INSERT INTO T VALUES (3), (4);
|
||||
ALTER TABLE T ADD COLUMN c_text TEXT DEFAULT 'Hello';
|
||||
INSERT INTO T VALUES (5), (6);
|
||||
ALTER TABLE T ALTER COLUMN c_text SET DEFAULT 'world',
|
||||
ALTER COLUMN c_int SET DEFAULT 1;
|
||||
INSERT INTO T VALUES (7), (8);
|
||||
SELECT * FROM T ORDER BY pk;
|
||||
pk | c_int | c_text
|
||||
----+-------+--------
|
||||
1 | -1 | Hello
|
||||
2 | -1 | Hello
|
||||
3 | -1 | Hello
|
||||
4 | -1 | Hello
|
||||
5 | -1 | Hello
|
||||
6 | -1 | Hello
|
||||
7 | 1 | world
|
||||
8 | 1 | world
|
||||
(8 rows)
|
||||
|
||||
-- Add an index
|
||||
CREATE INDEX i ON T(c_int, c_text);
|
||||
SELECT c_text FROM T WHERE c_int = -1;
|
||||
c_text
|
||||
--------
|
||||
Hello
|
||||
Hello
|
||||
Hello
|
||||
Hello
|
||||
Hello
|
||||
Hello
|
||||
(6 rows)
|
||||
|
||||
SELECT comp();
|
||||
comp
|
||||
-----------
|
||||
Unchanged
|
||||
(1 row)
|
||||
|
||||
DROP TABLE T;
|
||||
DROP FUNCTION set(name);
|
||||
DROP FUNCTION comp();
|
||||
DROP TABLE m;
|
||||
DROP TABLE has_volatile;
|
||||
DROP EVENT TRIGGER has_volatile_rewrite;
|
||||
DROP FUNCTION log_rewrite;
|
||||
DROP SCHEMA fast_default;
|
||||
@ -116,7 +116,7 @@ test: plancache limit plpgsql copy2 temp domain rangefuncs prepare without_oid c
|
||||
# ----------
|
||||
# Another group of parallel tests
|
||||
# ----------
|
||||
test: identity partition_join partition_prune reloptions hash_part indexing partition_aggregate
|
||||
test: identity partition_join partition_prune reloptions hash_part indexing partition_aggregate fast_default
|
||||
|
||||
# event triggers cannot run concurrently with any test that runs DDL
|
||||
test: event_trigger
|
||||
|
||||
@ -187,5 +187,6 @@ test: reloptions
|
||||
test: hash_part
|
||||
test: indexing
|
||||
test: partition_aggregate
|
||||
test: fast_default
|
||||
test: event_trigger
|
||||
test: stats
|
||||
|
||||
357
src/test/regress/sql/fast_default.sql
Normal file
357
src/test/regress/sql/fast_default.sql
Normal file
@ -0,0 +1,357 @@
|
||||
--
|
||||
-- ALTER TABLE ADD COLUMN DEFAULT test
|
||||
--
|
||||
|
||||
SET search_path = fast_default;
|
||||
CREATE SCHEMA fast_default;
|
||||
CREATE TABLE m(id OID);
|
||||
INSERT INTO m VALUES (NULL::OID);
|
||||
|
||||
CREATE FUNCTION set(tabname name) RETURNS VOID
|
||||
AS $$
|
||||
BEGIN
|
||||
UPDATE m
|
||||
SET id = (SELECT c.relfilenode
|
||||
FROM pg_class AS c, pg_namespace AS s
|
||||
WHERE c.relname = tabname
|
||||
AND c.relnamespace = s.oid
|
||||
AND s.nspname = 'fast_default');
|
||||
END;
|
||||
$$ LANGUAGE 'plpgsql';
|
||||
|
||||
CREATE FUNCTION comp() RETURNS TEXT
|
||||
AS $$
|
||||
BEGIN
|
||||
RETURN (SELECT CASE
|
||||
WHEN m.id = c.relfilenode THEN 'Unchanged'
|
||||
ELSE 'Rewritten'
|
||||
END
|
||||
FROM m, pg_class AS c, pg_namespace AS s
|
||||
WHERE c.relname = 't'
|
||||
AND c.relnamespace = s.oid
|
||||
AND s.nspname = 'fast_default');
|
||||
END;
|
||||
$$ LANGUAGE 'plpgsql';
|
||||
|
||||
CREATE FUNCTION log_rewrite() RETURNS event_trigger
|
||||
LANGUAGE plpgsql as
|
||||
$func$
|
||||
|
||||
declare
|
||||
this_schema text;
|
||||
begin
|
||||
select into this_schema relnamespace::regnamespace::text
|
||||
from pg_class
|
||||
where oid = pg_event_trigger_table_rewrite_oid();
|
||||
if this_schema = 'fast_default'
|
||||
then
|
||||
RAISE NOTICE 'rewriting table % for reason %',
|
||||
pg_event_trigger_table_rewrite_oid()::regclass,
|
||||
pg_event_trigger_table_rewrite_reason();
|
||||
end if;
|
||||
end;
|
||||
$func$;
|
||||
|
||||
CREATE TABLE has_volatile AS
|
||||
SELECT * FROM generate_series(1,10) id;
|
||||
|
||||
|
||||
CREATE EVENT TRIGGER has_volatile_rewrite
|
||||
ON table_rewrite
|
||||
EXECUTE PROCEDURE log_rewrite();
|
||||
|
||||
-- only the last of these should trigger a rewrite
|
||||
ALTER TABLE has_volatile ADD col1 int;
|
||||
ALTER TABLE has_volatile ADD col2 int DEFAULT 1;
|
||||
ALTER TABLE has_volatile ADD col3 timestamptz DEFAULT current_timestamp;
|
||||
ALTER TABLE has_volatile ADD col4 int DEFAULT (random() * 10000)::int;
|
||||
|
||||
|
||||
|
||||
-- Test a large sample of different datatypes
|
||||
CREATE TABLE T(pk INT NOT NULL PRIMARY KEY, c_int INT DEFAULT 1);
|
||||
|
||||
SELECT set('t');
|
||||
|
||||
INSERT INTO T VALUES (1), (2);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_bpchar BPCHAR(5) DEFAULT 'hello',
|
||||
ALTER COLUMN c_int SET DEFAULT 2;
|
||||
|
||||
INSERT INTO T VALUES (3), (4);
|
||||
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_text TEXT DEFAULT 'world',
|
||||
ALTER COLUMN c_bpchar SET DEFAULT 'dog';
|
||||
|
||||
INSERT INTO T VALUES (5), (6);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_date DATE DEFAULT '2016-06-02',
|
||||
ALTER COLUMN c_text SET DEFAULT 'cat';
|
||||
|
||||
INSERT INTO T VALUES (7), (8);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_timestamp TIMESTAMP DEFAULT '2016-09-01 12:00:00',
|
||||
ADD COLUMN c_timestamp_null TIMESTAMP,
|
||||
ALTER COLUMN c_date SET DEFAULT '2010-01-01';
|
||||
|
||||
INSERT INTO T VALUES (9), (10);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_array TEXT[]
|
||||
DEFAULT '{"This", "is", "the", "real", "world"}',
|
||||
ALTER COLUMN c_timestamp SET DEFAULT '1970-12-31 11:12:13',
|
||||
ALTER COLUMN c_timestamp_null SET DEFAULT '2016-09-29 12:00:00';
|
||||
|
||||
INSERT INTO T VALUES (11), (12);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_small SMALLINT DEFAULT -5,
|
||||
ADD COLUMN c_small_null SMALLINT,
|
||||
ALTER COLUMN c_array
|
||||
SET DEFAULT '{"This", "is", "no", "fantasy"}';
|
||||
|
||||
INSERT INTO T VALUES (13), (14);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_big BIGINT DEFAULT 180000000000018,
|
||||
ALTER COLUMN c_small SET DEFAULT 9,
|
||||
ALTER COLUMN c_small_null SET DEFAULT 13;
|
||||
|
||||
INSERT INTO T VALUES (15), (16);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_num NUMERIC DEFAULT 1.00000000001,
|
||||
ALTER COLUMN c_big SET DEFAULT -9999999999999999;
|
||||
|
||||
INSERT INTO T VALUES (17), (18);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_time TIME DEFAULT '12:00:00',
|
||||
ALTER COLUMN c_num SET DEFAULT 2.000000000000002;
|
||||
|
||||
INSERT INTO T VALUES (19), (20);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_interval INTERVAL DEFAULT '1 day',
|
||||
ALTER COLUMN c_time SET DEFAULT '23:59:59';
|
||||
|
||||
INSERT INTO T VALUES (21), (22);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_hugetext TEXT DEFAULT repeat('abcdefg',1000),
|
||||
ALTER COLUMN c_interval SET DEFAULT '3 hours';
|
||||
|
||||
INSERT INTO T VALUES (23), (24);
|
||||
|
||||
ALTER TABLE T ALTER COLUMN c_interval DROP DEFAULT,
|
||||
ALTER COLUMN c_hugetext SET DEFAULT repeat('poiuyt', 1000);
|
||||
|
||||
INSERT INTO T VALUES (25), (26);
|
||||
|
||||
ALTER TABLE T ALTER COLUMN c_bpchar DROP DEFAULT,
|
||||
ALTER COLUMN c_date DROP DEFAULT,
|
||||
ALTER COLUMN c_text DROP DEFAULT,
|
||||
ALTER COLUMN c_timestamp DROP DEFAULT,
|
||||
ALTER COLUMN c_array DROP DEFAULT,
|
||||
ALTER COLUMN c_small DROP DEFAULT,
|
||||
ALTER COLUMN c_big DROP DEFAULT,
|
||||
ALTER COLUMN c_num DROP DEFAULT,
|
||||
ALTER COLUMN c_time DROP DEFAULT,
|
||||
ALTER COLUMN c_hugetext DROP DEFAULT;
|
||||
|
||||
INSERT INTO T VALUES (27), (28);
|
||||
|
||||
SELECT pk, c_int, c_bpchar, c_text, c_date, c_timestamp,
|
||||
c_timestamp_null, c_array, c_small, c_small_null,
|
||||
c_big, c_num, c_time, c_interval,
|
||||
c_hugetext = repeat('abcdefg',1000) as c_hugetext_origdef,
|
||||
c_hugetext = repeat('poiuyt', 1000) as c_hugetext_newdef
|
||||
FROM T ORDER BY pk;
|
||||
|
||||
SELECT comp();
|
||||
|
||||
DROP TABLE T;
|
||||
|
||||
-- Test expressions in the defaults
|
||||
CREATE OR REPLACE FUNCTION foo(a INT) RETURNS TEXT AS $$
|
||||
DECLARE res TEXT := '';
|
||||
i INT;
|
||||
BEGIN
|
||||
i := 0;
|
||||
WHILE (i < a) LOOP
|
||||
res := res || chr(ascii('a') + i);
|
||||
i := i + 1;
|
||||
END LOOP;
|
||||
RETURN res;
|
||||
END; $$ LANGUAGE PLPGSQL STABLE;
|
||||
|
||||
CREATE TABLE T(pk INT NOT NULL PRIMARY KEY, c_int INT DEFAULT LENGTH(foo(6)));
|
||||
|
||||
SELECT set('t');
|
||||
|
||||
INSERT INTO T VALUES (1), (2);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_bpchar BPCHAR(5) DEFAULT foo(4),
|
||||
ALTER COLUMN c_int SET DEFAULT LENGTH(foo(8));
|
||||
|
||||
INSERT INTO T VALUES (3), (4);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_text TEXT DEFAULT foo(6),
|
||||
ALTER COLUMN c_bpchar SET DEFAULT foo(3);
|
||||
|
||||
INSERT INTO T VALUES (5), (6);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_date DATE
|
||||
DEFAULT '2016-06-02'::DATE + LENGTH(foo(10)),
|
||||
ALTER COLUMN c_text SET DEFAULT foo(12);
|
||||
|
||||
INSERT INTO T VALUES (7), (8);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_timestamp TIMESTAMP
|
||||
DEFAULT '2016-09-01'::DATE + LENGTH(foo(10)),
|
||||
ALTER COLUMN c_date
|
||||
SET DEFAULT '2010-01-01'::DATE - LENGTH(foo(4));
|
||||
|
||||
INSERT INTO T VALUES (9), (10);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_array TEXT[]
|
||||
DEFAULT ('{"This", "is", "' || foo(4) ||
|
||||
'","the", "real", "world"}')::TEXT[],
|
||||
ALTER COLUMN c_timestamp
|
||||
SET DEFAULT '1970-12-31'::DATE + LENGTH(foo(30));
|
||||
|
||||
INSERT INTO T VALUES (11), (12);
|
||||
|
||||
ALTER TABLE T ALTER COLUMN c_int DROP DEFAULT,
|
||||
ALTER COLUMN c_array
|
||||
SET DEFAULT ('{"This", "is", "' || foo(1) ||
|
||||
'", "fantasy"}')::text[];
|
||||
|
||||
INSERT INTO T VALUES (13), (14);
|
||||
|
||||
ALTER TABLE T ALTER COLUMN c_bpchar DROP DEFAULT,
|
||||
ALTER COLUMN c_date DROP DEFAULT,
|
||||
ALTER COLUMN c_text DROP DEFAULT,
|
||||
ALTER COLUMN c_timestamp DROP DEFAULT,
|
||||
ALTER COLUMN c_array DROP DEFAULT;
|
||||
|
||||
INSERT INTO T VALUES (15), (16);
|
||||
|
||||
SELECT * FROM T;
|
||||
|
||||
SELECT comp();
|
||||
|
||||
DROP TABLE T;
|
||||
|
||||
DROP FUNCTION foo(INT);
|
||||
|
||||
-- Fall back to full rewrite for volatile expressions
|
||||
CREATE TABLE T(pk INT NOT NULL PRIMARY KEY);
|
||||
|
||||
INSERT INTO T VALUES (1);
|
||||
|
||||
SELECT set('t');
|
||||
|
||||
-- now() is stable, because it returns the transaction timestamp
|
||||
ALTER TABLE T ADD COLUMN c1 TIMESTAMP DEFAULT now();
|
||||
|
||||
SELECT comp();
|
||||
|
||||
-- clock_timestamp() is volatile
|
||||
ALTER TABLE T ADD COLUMN c2 TIMESTAMP DEFAULT clock_timestamp();
|
||||
|
||||
SELECT comp();
|
||||
|
||||
DROP TABLE T;
|
||||
|
||||
-- Simple querie
|
||||
CREATE TABLE T (pk INT NOT NULL PRIMARY KEY);
|
||||
|
||||
SELECT set('t');
|
||||
|
||||
INSERT INTO T SELECT * FROM generate_series(1, 10) a;
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_bigint BIGINT NOT NULL DEFAULT -1;
|
||||
|
||||
INSERT INTO T SELECT b, b - 10 FROM generate_series(11, 20) a(b);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_text TEXT DEFAULT 'hello';
|
||||
|
||||
INSERT INTO T SELECT b, b - 10, (b + 10)::text FROM generate_series(21, 30) a(b);
|
||||
|
||||
-- WHERE clause
|
||||
SELECT c_bigint, c_text FROM T WHERE c_bigint = -1 LIMIT 1;
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE)
|
||||
SELECT c_bigint, c_text FROM T WHERE c_bigint = -1 LIMIT 1;
|
||||
|
||||
SELECT c_bigint, c_text FROM T WHERE c_text = 'hello' LIMIT 1;
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE) SELECT c_bigint, c_text FROM T WHERE c_text = 'hello' LIMIT 1;
|
||||
|
||||
|
||||
-- COALESCE
|
||||
SELECT COALESCE(c_bigint, pk), COALESCE(c_text, pk::text)
|
||||
FROM T
|
||||
ORDER BY pk LIMIT 10;
|
||||
|
||||
-- Aggregate function
|
||||
SELECT SUM(c_bigint), MAX(c_text), MIN(c_text) FROM T;
|
||||
|
||||
-- ORDER BY
|
||||
SELECT * FROM T ORDER BY c_bigint, c_text, pk LIMIT 10;
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE)
|
||||
SELECT * FROM T ORDER BY c_bigint, c_text, pk LIMIT 10;
|
||||
|
||||
-- LIMIT
|
||||
SELECT * FROM T WHERE c_bigint > -1 ORDER BY c_bigint, c_text, pk LIMIT 10;
|
||||
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE)
|
||||
SELECT * FROM T WHERE c_bigint > -1 ORDER BY c_bigint, c_text, pk LIMIT 10;
|
||||
|
||||
-- DELETE with RETURNING
|
||||
DELETE FROM T WHERE pk BETWEEN 10 AND 20 RETURNING *;
|
||||
EXPLAIN (VERBOSE TRUE, COSTS FALSE)
|
||||
DELETE FROM T WHERE pk BETWEEN 10 AND 20 RETURNING *;
|
||||
|
||||
-- UPDATE
|
||||
UPDATE T SET c_text = '"' || c_text || '"' WHERE pk < 10;
|
||||
SELECT * FROM T WHERE c_text LIKE '"%"' ORDER BY PK;
|
||||
|
||||
SELECT comp();
|
||||
|
||||
DROP TABLE T;
|
||||
|
||||
|
||||
-- Combine with other DDL
|
||||
CREATE TABLE T(pk INT NOT NULL PRIMARY KEY);
|
||||
|
||||
SELECT set('t');
|
||||
|
||||
INSERT INTO T VALUES (1), (2);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_int INT NOT NULL DEFAULT -1;
|
||||
|
||||
INSERT INTO T VALUES (3), (4);
|
||||
|
||||
ALTER TABLE T ADD COLUMN c_text TEXT DEFAULT 'Hello';
|
||||
|
||||
INSERT INTO T VALUES (5), (6);
|
||||
|
||||
ALTER TABLE T ALTER COLUMN c_text SET DEFAULT 'world',
|
||||
ALTER COLUMN c_int SET DEFAULT 1;
|
||||
|
||||
INSERT INTO T VALUES (7), (8);
|
||||
|
||||
SELECT * FROM T ORDER BY pk;
|
||||
|
||||
-- Add an index
|
||||
CREATE INDEX i ON T(c_int, c_text);
|
||||
|
||||
SELECT c_text FROM T WHERE c_int = -1;
|
||||
|
||||
SELECT comp();
|
||||
|
||||
DROP TABLE T;
|
||||
DROP FUNCTION set(name);
|
||||
DROP FUNCTION comp();
|
||||
DROP TABLE m;
|
||||
DROP TABLE has_volatile;
|
||||
DROP EVENT TRIGGER has_volatile_rewrite;
|
||||
DROP FUNCTION log_rewrite;
|
||||
DROP SCHEMA fast_default;
|
||||
Reference in New Issue
Block a user