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CREATE TABLE t1 (i INT AUTO_INCREMENT, c VARCHAR(1), KEY(i), KEY(c,i)) ENGINE=MyISAM;
INSERT INTO t1 (c) select mid("abcdefgh", mod(seq,8)+1, 1) from seq_1_to_256;
explain SELECT 1 FROM t1 AS alias1, t1 AS alias2, t1 AS alias3
WHERE alias1.c = alias2.c OR alias1.i <= 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE alias2 index c c 8 NULL 256 Using index
1 SIMPLE alias3 index NULL i 4 NULL 256 Using index; Using join buffer (flat, BNL join)
1 SIMPLE alias1 ALL i,c NULL NULL NULL 256 Range checked for each record (index map: 0x3)
set @old_dbug=@@session.debug_dbug;
SET debug_dbug="+d,kill_join_init_read_record";
SELECT 1 FROM t1 AS alias1, t1 AS alias2, t1 AS alias3
WHERE alias1.c = alias2.c OR alias1.i <= 1
;
ERROR 70100: Query execution was interrupted
SET debug_dbug=@old_dbug;
DROP TABLE t1;
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