# Copyright (c) 2021-2025, PostgreSQL Global Development Group
# Test WAL replay when some operation has skipped WAL. # # These tests exercise code that once violated the mandate described in # src/backend/access/transam/README section "Skipping WAL for New # RelFileLocator". The tests work by committing some transactions, initiating an # immediate shutdown, and confirming that the expected data survives recovery. # For many years, individual commands made the decision to skip WAL, hence the # frequent appearance of COPY in these tests.
use strict;
use warnings FATAL => 'all';
use PostgreSQL::Test::Cluster;
use PostgreSQL::Test::Utils;
use Test::More;
sub check_orphan_relfilenodes
{
local $Test::Builder::Level = $Test::Builder::Level + 1;
my ($node, $test_name) = @_;
my $db_oid = $node->safe_psql('postgres', "SELECT oid FROM pg_database WHERE datname = 'postgres'");
my $prefix = "base/$db_oid/";
my $filepaths_referenced = $node->safe_psql( 'postgres', "
SELECT pg_relation_filepath(oid) FROM pg_class
WHERE reltablespace = 0 AND relpersistence <> 't' AND
pg_relation_filepath(oid) IS NOT NULL;");
is_deeply(
[
sort(map { "$prefix$_" }
grep(/^[0-9]+$/, slurp_dir($node->data_dir . "/$prefix")))
],
[ sort split /\n/, $filepaths_referenced ],
$test_name);
return;
}
# We run this same test suite for both wal_level=minimal and replica.
sub run_wal_optimize
{
my $wal_level = shift;
my $node = PostgreSQL::Test::Cluster->new("node_$wal_level");
$node->init;
$node->append_conf( 'postgresql.conf', qq(
wal_level = $wal_level
max_prepared_transactions = 1
wal_log_hints = on
wal_skip_threshold = 0 #wal_debug = on
));
$node->start;
# Setup
my $tablespace_dir = $node->basedir . '/tablespace_other';
mkdir($tablespace_dir);
my $result;
# Test redo of CREATE TABLESPACE.
$node->safe_psql( 'postgres', "
CREATE TABLE moved (id int);
INSERT INTO moved VALUES (1);
CREATE TABLESPACE other LOCATION '$tablespace_dir';
BEGIN;
ALTER TABLE moved SET TABLESPACE other;
CREATE TABLE originated (id int);
INSERT INTO originated VALUES (1);
CREATE UNIQUE INDEX ON originated(id) TABLESPACE other;
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM moved;");
is($result, qq(1), "wal_level = $wal_level, CREATE+SET TABLESPACE");
$result = $node->safe_psql( 'postgres', "
INSERT INTO originated VALUES (1) ON CONFLICT (id)
DO UPDATE set id = originated.id + 1
RETURNING id;");
is($result, qq(2), "wal_level = $wal_level, CREATE TABLESPACE, CREATE INDEX");
# Test direct truncation optimization. No tuples.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE trunc (id serial PRIMARY KEY);
TRUNCATE trunc;
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM trunc;");
is($result, qq(0), "wal_level = $wal_level, TRUNCATE with empty table");
# Test truncation with inserted tuples within the same transaction. # Tuples inserted after the truncation should be seen.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE trunc_ins (id serial PRIMARY KEY);
INSERT INTO trunc_ins VALUES (DEFAULT);
TRUNCATE trunc_ins;
INSERT INTO trunc_ins VALUES (DEFAULT);
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*), min(id) FROM trunc_ins;");
is($result, qq(1|2), "wal_level = $wal_level, TRUNCATE INSERT");
# Same for prepared transaction. # Tuples inserted after the truncation should be seen.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE twophase (id serial PRIMARY KEY);
INSERT INTO twophase VALUES (DEFAULT);
TRUNCATE twophase;
INSERT INTO twophase VALUES (DEFAULT);
PREPARE TRANSACTION 't';
COMMIT PREPARED 't';");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*), min(id) FROM trunc_ins;");
is($result, qq(1|2), "wal_level = $wal_level, TRUNCATE INSERT PREPARE");
# Writing WAL at end of xact, instead of syncing.
$node->safe_psql( 'postgres', "
SET wal_skip_threshold = '1GB';
BEGIN;
CREATE TABLE noskip (id serial PRIMARY KEY);
INSERT INTO noskip (SELECT FROM generate_series(1, 20000) a) ;
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM noskip;");
is($result, qq(20000), "wal_level = $wal_level, end-of-xact WAL");
# Data file for COPY query in subsequent tests
my $basedir = $node->basedir;
my $copy_file = "$basedir/copy_data.txt";
PostgreSQL::Test::Utils::append_to_file(
$copy_file, qq(20000,30000 20001,30001 20002,30002));
# Test truncation with inserted tuples using both INSERT and COPY. Tuples # inserted after the truncation should be seen.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE ins_trunc (id serial PRIMARY KEY, id2 int);
INSERT INTO ins_trunc VALUES (DEFAULT, generate_series(1,10000));
TRUNCATE ins_trunc;
INSERT INTO ins_trunc (id, id2) VALUES (DEFAULT, 10000);
COPY ins_trunc FROM '$copy_file' DELIMITER ',';
INSERT INTO ins_trunc (id, id2) VALUES (DEFAULT, 10000);
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM ins_trunc;");
is($result, qq(5), "wal_level = $wal_level, TRUNCATE COPY INSERT");
# Test truncation with inserted tuples using COPY. Tuples copied after # the truncation should be seen.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE trunc_copy (id serial PRIMARY KEY, id2 int);
INSERT INTO trunc_copy VALUES (DEFAULT, generate_series(1,3000));
TRUNCATE trunc_copy;
COPY trunc_copy FROM '$copy_file' DELIMITER ',';
COMMIT;");
$node->stop('immediate');
$node->start;
$result =
$node->safe_psql('postgres', "SELECT count(*) FROM trunc_copy;");
is($result, qq(3), "wal_level = $wal_level, TRUNCATE COPY");
# Like previous test, but rollback SET TABLESPACE in a subtransaction.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE spc_abort (id serial PRIMARY KEY, id2 int);
INSERT INTO spc_abort VALUES (DEFAULT, generate_series(1,3000));
TRUNCATE spc_abort;
SAVEPOINT s;
ALTER TABLE spc_abort SET TABLESPACE other; ROLLBACK TO s;
COPY spc_abort FROM '$copy_file' DELIMITER ',';
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM spc_abort;");
is($result, qq(3), "wal_level = $wal_level, SET TABLESPACE abort subtransaction");
# in different subtransaction patterns
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE spc_commit (id serial PRIMARY KEY, id2 int);
INSERT INTO spc_commit VALUES (DEFAULT, generate_series(1,3000));
TRUNCATE spc_commit;
SAVEPOINT s; ALTER TABLE spc_commit SET TABLESPACE other; RELEASE s;
COPY spc_commit FROM '$copy_file' DELIMITER ',';
COMMIT;");
$node->stop('immediate');
$node->start;
$result =
$node->safe_psql('postgres', "SELECT count(*) FROM spc_commit;");
is($result, qq(3), "wal_level = $wal_level, SET TABLESPACE commit subtransaction");
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE spc_nest (id serial PRIMARY KEY, id2 int);
INSERT INTO spc_nest VALUES (DEFAULT, generate_series(1,3000));
TRUNCATE spc_nest;
SAVEPOINT s;
ALTER TABLE spc_nest SET TABLESPACE other;
SAVEPOINT s2;
ALTER TABLE spc_nest SET TABLESPACE pg_default;
ROLLBACK TO s2;
SAVEPOINT s2;
ALTER TABLE spc_nest SET TABLESPACE pg_default;
RELEASE s2;
ROLLBACK TO s;
COPY spc_nest FROM '$copy_file' DELIMITER ',';
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM spc_nest;");
is($result, qq(3), "wal_level = $wal_level, SET TABLESPACE nested subtransaction");
$node->safe_psql( 'postgres', "
CREATE TABLE spc_hint (id int);
INSERT INTO spc_hint VALUES (1);
BEGIN;
ALTER TABLE spc_hint SET TABLESPACE other;
CHECKPOINT;
SELECT * FROM spc_hint; -- set hint bit
INSERT INTO spc_hint VALUES (2);
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM spc_hint;");
is($result, qq(2), "wal_level = $wal_level, SET TABLESPACE, hint bit");
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE idx_hint (c int PRIMARY KEY);
SAVEPOINT q; INSERT INTO idx_hint VALUES (1); ROLLBACK TO q;
CHECKPOINT;
INSERT INTO idx_hint VALUES (1); -- set index hint bit
INSERT INTO idx_hint VALUES (2);
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->psql('postgres',);
my ($ret, $stdout, $stderr) =
$node->psql('postgres', "INSERT INTO idx_hint VALUES (2);");
is($ret, qq(3), "wal_level = $wal_level, unique index LP_DEAD");
like(
$stderr,
qr/violates unique/, "wal_level = $wal_level, unique index LP_DEAD message");
# UPDATE touches two buffers for one row.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE upd (id serial PRIMARY KEY, id2 int);
INSERT INTO upd (id, id2) VALUES (DEFAULT, generate_series(1,10000));
COPY upd FROM '$copy_file' DELIMITER ',';
UPDATE upd SET id2 = id2 + 1;
DELETE FROM upd;
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM upd;");
is($result, qq(0), "wal_level = $wal_level, UPDATE touches two buffers for one row");
# Test consistency of COPY with INSERT for table created in the same # transaction.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE ins_copy (id serial PRIMARY KEY, id2 int);
INSERT INTO ins_copy VALUES (DEFAULT, 1);
COPY ins_copy FROM '$copy_file' DELIMITER ',';
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM ins_copy;");
is($result, qq(4), "wal_level = $wal_level, INSERT COPY");
# Test consistency of COPY that inserts more to the same table using # triggers. If the INSERTS from the trigger go to the same block data # is copied to, and the INSERTs are WAL-logged, WAL replay will fail when # it tries to replay the WAL record but the "before" image doesn't match, # because not all changes were WAL-logged.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE ins_trig (id serial PRIMARY KEY, id2 text);
CREATE FUNCTION ins_trig_before_row_trig() RETURNS trigger
LANGUAGE plpgsql as \$\$
BEGIN
IF new.id2 NOT LIKE 'triggered%' THEN
INSERT INTO ins_trig
VALUES (DEFAULT, 'triggered row before' || NEW.id2);
END IF;
RETURN NEW;
END; \$\$;
CREATE FUNCTION ins_trig_after_row_trig() RETURNS trigger
LANGUAGE plpgsql as \$\$
BEGIN
IF new.id2 NOT LIKE 'triggered%' THEN
INSERT INTO ins_trig
VALUES (DEFAULT, 'triggered row after' || NEW.id2);
END IF;
RETURN NEW;
END; \$\$;
CREATE TRIGGER ins_trig_before_row_insert
BEFORE INSERT ON ins_trig
FOR EACH ROW EXECUTE PROCEDURE ins_trig_before_row_trig();
CREATE TRIGGER ins_trig_after_row_insert
AFTER INSERT ON ins_trig
FOR EACH ROW EXECUTE PROCEDURE ins_trig_after_row_trig();
COPY ins_trig FROM '$copy_file' DELIMITER ',';
COMMIT;");
$node->stop('immediate');
$node->start;
$result = $node->safe_psql('postgres', "SELECT count(*) FROM ins_trig;");
is($result, qq(9), "wal_level = $wal_level, COPY with INSERT triggers");
# Test consistency of INSERT, COPY and TRUNCATE in same transaction block # with TRUNCATE triggers.
$node->safe_psql( 'postgres', "
BEGIN;
CREATE TABLE trunc_trig (id serial PRIMARY KEY, id2 text);
CREATE FUNCTION trunc_trig_before_stat_trig() RETURNS trigger
LANGUAGE plpgsql as \$\$
BEGIN
INSERT INTO trunc_trig VALUES (DEFAULT, 'triggered stat before');
RETURN NULL;
END; \$\$;
CREATE FUNCTION trunc_trig_after_stat_trig() RETURNS trigger
LANGUAGE plpgsql as \$\$
BEGIN
INSERT INTO trunc_trig VALUES (DEFAULT, 'triggered stat before');
RETURN NULL;
END; \$\$;
CREATE TRIGGER trunc_trig_before_stat_truncate
BEFORE TRUNCATE ON trunc_trig
FOR EACH STATEMENT EXECUTE PROCEDURE trunc_trig_before_stat_trig();
CREATE TRIGGER trunc_trig_after_stat_truncate
AFTER TRUNCATE ON trunc_trig
FOR EACH STATEMENT EXECUTE PROCEDURE trunc_trig_after_stat_trig();
INSERT INTO trunc_trig VALUES (DEFAULT, 1);
TRUNCATE trunc_trig;
COPY trunc_trig FROM '$copy_file' DELIMITER ',';
COMMIT;");
$node->stop('immediate');
$node->start;
$result =
$node->safe_psql('postgres', "SELECT count(*) FROM trunc_trig;");
is($result, qq(4), "wal_level = $wal_level, TRUNCATE COPY with TRUNCATE triggers");
# Test redo of temp table creation.
$node->safe_psql( 'postgres', "
CREATE TEMP TABLE temp (id serial PRIMARY KEY, id2 text);");
$node->stop('immediate');
$node->start;
check_orphan_relfilenodes($node, "wal_level = $wal_level, no orphan relfilenode remains");
return;
}
# Run same test suite for multiple wal_level values.
run_wal_optimize("minimal");
run_wal_optimize("replica");
done_testing();
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