SET autocommit = 0;
START TRANSACTION;

*** Delete a row and re-insert with same `pk`:

*** Disabling result log
SELECT @pk:=`pk`,
@unique1:=`int1_unique`,
@unique2:=`int2_unique`
    FROM t1 WHERE `pk` MOD 5 = 4 AND `pk` > 900 AND `is_consistent` = 1 LIMIT 1 FOR UPDATE;
*** Enabling result log
DELETE FROM t1 WHERE `pk` = @pk;
*** Doing insert of row with pk = @pk if above statement succeeded (query log disabled)...
COMMIT;
START TRANSACTION;

*** Delete a row and re-insert with `pk` = NULL:

*** Disabling result log
SELECT @pk:=`pk`,
@unique1:=`int1_unique`,
@unique2:=`int2_unique`
    FROM t1 WHERE `pk` MOD 5 = 4 AND `pk` > 901 AND `is_consistent` = 1 LIMIT 1 FOR UPDATE;
*** Enabling result log
DELETE FROM t1 WHERE `pk` = @pk;
*** Doing insert of row with pk = NULL if above statement succeeded (query log disabled)...
COMMIT;
START TRANSACTION;

*** Delete up to two (2) "consistent" rows (zero-sum; table sum unchanged)

DELETE FROM t1 WHERE `pk` > 902 AND `pk` MOD 5 = 3 AND `is_consistent` = 1 LIMIT 2;
COMMIT;