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# When a tuple that has been updated is locked, the locking command must
# traverse the update chain; thus, a DELETE (on the newer version of the tuple)
# should not be able to proceed until the lock has been released. An UPDATE
# that changes the key should not be allowed to continue either; but an UPDATE
# that doesn't modify the key should be able to continue immediately.
setup
{
CREATE TABLE foo (
key int,
value int,
PRIMARY KEY (key) INCLUDE (value)
);
INSERT INTO foo VALUES (1, 1);
}
teardown
{
DROP TABLE foo;
}
session s1
step s1b { BEGIN ISOLATION LEVEL REPEATABLE READ; }
step s1s { SELECT * FROM foo; } # obtain snapshot
step s1l { SELECT * FROM foo FOR KEY SHARE; } # obtain lock
step s1c { COMMIT; }
session s2
step s2b { BEGIN; }
step s2u { UPDATE foo SET value = 2 WHERE key = 1; }
step s2c { COMMIT; }
step s2d1 { DELETE FROM foo WHERE key = 1; }
step s2d2 { UPDATE foo SET key = 3 WHERE key = 1; }
step s2d3 { UPDATE foo SET value = 3 WHERE key = 1; }
permutation s1b s2b s1s s2u s1l s2c s2d1 s1c
permutation s1b s2b s1s s2u s1l s2c s2d2 s1c
permutation s1b s2b s1s s2u s1l s2c s2d3 s1c
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