src/test/isolation/specs/multiple-row-versions.spec

# Multiple Row Versions test
#
# This test is designed to cover some code paths which only occur with
# four or more transactions interacting with particular timings.
#
# Due to long permutation setup time, we are only testing one specific
# permutation, which should get a serialization error.

setup
{
 CREATE TABLE t (id int NOT NULL, txt text) WITH (fillfactor=50);
 INSERT INTO t (id)
   SELECT x FROM (SELECT * FROM generate_series(1, 1000000)) a(x);
 ALTER TABLE t ADD PRIMARY KEY (id);
}

teardown
{
 DROP TABLE t;
}

session s1
setup		{ BEGIN ISOLATION LEVEL SERIALIZABLE; }
step rx1	{ SELECT * FROM t WHERE id = 1000000; }
# delay until after T3 commits
step wz1	{ UPDATE t SET txt = 'a' WHERE id = 1; }
step c1		{ COMMIT; }

session s2
setup		{ BEGIN ISOLATION LEVEL SERIALIZABLE; }
step wx2	{ UPDATE t SET txt = 'b' WHERE id = 1000000; }
step c2		{ COMMIT; }

session s3
setup		{ BEGIN ISOLATION LEVEL SERIALIZABLE; }
step wx3	{ UPDATE t SET txt = 'c' WHERE id = 1000000; }
step ry3	{ SELECT * FROM t WHERE id = 500000; }
# delay until after T4 commits
step c3		{ COMMIT; }

session s4
setup		{ BEGIN ISOLATION LEVEL SERIALIZABLE; }
step wy4	{ UPDATE t SET txt = 'd' WHERE id = 500000; }
step rz4	{ SELECT * FROM t WHERE id = 1; }
step c4		{ COMMIT; }

permutation rx1 wx2 c2 wx3 ry3 wy4 rz4 c4 c3 wz1 c1