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# Test SKIP LOCKED with tuple locks.
setup
{
CREATE TABLE queue (
id int PRIMARY KEY,
data text NOT NULL,
status text NOT NULL
);
INSERT INTO queue VALUES (1, 'foo', 'NEW'), (2, 'bar', 'NEW');
}
teardown
{
DROP TABLE queue;
}
session s1
setup { BEGIN; }
step s1a { SELECT * FROM queue ORDER BY id FOR UPDATE LIMIT 1; }
step s1b { COMMIT; }
session s2
setup { BEGIN; }
step s2a { SELECT * FROM queue ORDER BY id FOR UPDATE LIMIT 1; }
step s2b { COMMIT; }
session s3
setup { BEGIN; }
step s3a { SELECT * FROM queue ORDER BY id FOR UPDATE SKIP LOCKED LIMIT 1; }
step s3b { COMMIT; }
# s3 skips to the second record because it can't obtain the tuple lock
# (s2 holds the tuple lock because it is next in line to obtain the
# row lock, and s1 holds the row lock)
permutation s1a s2a s3a s1b s2b s3b
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