table type possible_keys key key_len ref rows Extra t1 ref a a 5 const 3 where used; Using index table type possible_keys key key_len ref rows Extra t1 ref a,b a 9 const,const 1 where used; Using index table type possible_keys key key_len ref rows Extra t1 ref a,b a 9 const,const 1 where used; Using index table type possible_keys key key_len ref rows Extra t1 const a,b a 9 const,const 1 table type possible_keys key key_len ref rows Extra t1 index NULL a 9 NULL 12 where used; Using index table type possible_keys key key_len ref rows Extra t1 range a,b a 9 NULL 3 where used; Using index table type possible_keys key key_len ref rows Extra t1 ref a,b b 4 const 2 where used table type possible_keys key key_len ref rows Extra t1 ref a,b a 5 const 3 where used; Using index table type possible_keys key key_len ref rows Extra t1 range a,b a 9 NULL 2 where used; Using index table type possible_keys key key_len ref rows Extra t1 range a a 5 NULL 1 where used; Using index table type possible_keys key key_len ref rows Extra t1 range a a 5 NULL 1 where used; Using index a b NULL 7 NULL 9 NULL 9 a b NULL 7 a b 1 1 2 2 a b 1 1 2 2 a b NULL 9 NULL 9 a b NULL 7 7 7 a b NULL 7 NULL 9 NULL 9 table type possible_keys key key_len ref rows Extra t1 ref a,b a 5 const 3 where used table type possible_keys key key_len ref rows Extra t1 ref a,b a 5 const 3 where used table type possible_keys key key_len ref rows Extra t1 ref a,b a 5 const 3 where used table type possible_keys key key_len ref rows Extra t1 ref a,b a 5 const 1 where used table type possible_keys key key_len ref rows Extra t1 ALL NULL NULL NULL NULL 12 where used table type possible_keys key key_len ref rows Extra t1 range a,b a 5 NULL 12 where used table type possible_keys key key_len ref rows Extra t1 range a,b a 5 NULL 4 where used table type possible_keys key key_len ref rows Extra t1 ref a,b a 5 const 3 where used table type possible_keys key key_len ref rows Extra t1 ref a,b a 5 const 3 where used table type possible_keys key key_len ref rows Extra t1 range a a 5 NULL 1 where used table type possible_keys key key_len ref rows Extra t1 range a,b a 5 NULL 4 where used table type possible_keys key key_len ref rows Extra t1 range a a 5 NULL 1 where used table type possible_keys key key_len ref rows Extra t1 range b b 12 NULL 1 where used a b c NULL 7 0 NULL 9 0 NULL 9 0 a b c NULL 7 0 a b c 1 1 0 2 2 0 a b c 1 1 0 2 2 0 a b c NULL 9 0 NULL 9 0 a b c NULL 7 0 7 7 0 a b c NULL 7 0 NULL 9 0 NULL 9 0 a b c 6 6 0 table type possible_keys key key_len ref rows Extra t1 ref idx1 idx1 5 const 1 where used table type possible_keys key key_len ref rows Extra t1 const idx1 idx1 5 const 1 id 101 102 105 106 109 110 id 101 102 105 106 109 110 id uniq_id 3 1 4 2 7 3 8 4 id uniq_id 3 1 4 2 7 3 8 4