1221
1223
INSERT INTO t2 ( a, b, c ) VALUES ( 1, NULL, 2 ), ( 1, 3, 4 ), ( 1, 4, 4 );
1222
1224
EXPLAIN SELECT MIN(b), MIN(c) FROM t2 WHERE a = 1;
1223
1225
id select_type table type possible_keys key key_len ref rows Extra
1225
1227
SELECT MIN(b), MIN(c) FROM t2 WHERE a = 1;