Parsed test spec with 2 sessions

starting permutation: rx1 wy1 c1 ry2 wx2 c2
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c1: COMMIT;
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    1
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c2: COMMIT;

starting permutation: rx1 wy1 ry2 c1 wx2 c2
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step c1: COMMIT;
step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
ERROR:  could not serialize access due to read/write dependencies among transactions
step c2: COMMIT;

starting permutation: rx1 wy1 ry2 wx2 c1 c2
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c1: COMMIT;
step c2: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: rx1 wy1 ry2 wx2 c2 c1
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c2: COMMIT;
step c1: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: rx1 ry2 wy1 c1 wx2 c2
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c1: COMMIT;
step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
ERROR:  could not serialize access due to read/write dependencies among transactions
step c2: COMMIT;

starting permutation: rx1 ry2 wy1 wx2 c1 c2
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c1: COMMIT;
step c2: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: rx1 ry2 wy1 wx2 c2 c1
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c2: COMMIT;
step c1: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: rx1 ry2 wx2 wy1 c1 c2
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c1: COMMIT;
step c2: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: rx1 ry2 wx2 wy1 c2 c1
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c2: COMMIT;
step c1: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: rx1 ry2 wx2 c2 wy1 c1
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c2: COMMIT;
step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
ERROR:  could not serialize access due to read/write dependencies among transactions
step c1: COMMIT;

starting permutation: ry2 rx1 wy1 c1 wx2 c2
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c1: COMMIT;
step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
ERROR:  could not serialize access due to read/write dependencies among transactions
step c2: COMMIT;

starting permutation: ry2 rx1 wy1 wx2 c1 c2
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c1: COMMIT;
step c2: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: ry2 rx1 wy1 wx2 c2 c1
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c2: COMMIT;
step c1: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: ry2 rx1 wx2 wy1 c1 c2
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c1: COMMIT;
step c2: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: ry2 rx1 wx2 wy1 c2 c1
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c2: COMMIT;
step c1: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: ry2 rx1 wx2 c2 wy1 c1
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c2: COMMIT;
step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
ERROR:  could not serialize access due to read/write dependencies among transactions
step c1: COMMIT;

starting permutation: ry2 wx2 rx1 wy1 c1 c2
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c1: COMMIT;
step c2: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: ry2 wx2 rx1 wy1 c2 c1
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c2: COMMIT;
step c1: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: ry2 wx2 rx1 c2 wy1 c1
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    0
(1 row)

step c2: COMMIT;
step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
ERROR:  could not serialize access due to read/write dependencies among transactions
step c1: COMMIT;

starting permutation: ry2 wx2 c2 rx1 wy1 c1
step ry2: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:30';
count
-----
    0
(1 row)

step wx2: UPDATE room_reservation SET start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 13:30', end_time = TIMESTAMP WITH TIME ZONE '2010-04-01 14:30' WHERE room_id = '101' AND start_time = TIMESTAMP WITH TIME ZONE '2010-04-01 10:00';
step c2: COMMIT;
step rx1: SELECT count(*) FROM room_reservation WHERE room_id = '101' AND start_time < TIMESTAMP WITH TIME ZONE '2010-04-01 14:00' AND end_time > TIMESTAMP WITH TIME ZONE '2010-04-01 13:00';
count
-----
    1
(1 row)

step wy1: INSERT INTO room_reservation VALUES ('101', TIMESTAMP WITH TIME ZONE '2010-04-01 13:00', TIMESTAMP WITH TIME ZONE '2010-04-01 14:00', 'Carol');
step c1: COMMIT;