id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE schedules index_merge idspectacle_2, idcontact, idcontact_festival idcontact, idcontact_festival 5, 5 301 Using union(idcontact, idcontact_festival); Using where; Using temporary
1 SIMPLE spectacles eq_ref PRIMARY PRIMARY 4 theatreok_dev.schedules.idspectacle 1 Using where