id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> system 0 const row not found
1 PRIMARY clients ALL 1 Using temporary; Using filesort
1 PRIMARY <derived3> ALL 1 (null)
3 DERIVED messages ALL 31 Using where; Using temporary; Using filesort
2 DERIVED messages ALL 31 Using where; Using temporary; Using filesort
---------
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY clients index PRIMARY 4 1 Using temporary; Using filesort
3 DEPENDENT SUBQUERY mes_open ALL 31 Using where
2 DEPENDENT SUBQUERY mes_new ALL 31 Using where