A Database Error Occurred

Error Number: 1055

Expression #2 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'freegames4rest.games_category.category' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

SELECT `game_id`, `category` FROM (`games_category`) WHERE `game_id` IN ('monument_builders_statue_of_liberty', 'the_bluecoats_north_vs_south', 'the_princess_case_a_royal_scoop', 'monument_builders_titanic', 'monument_builder_eiffel_tower', 'spider_mania_solitaire', 'xiii_lost_identity', 'aladin_and_the_wonderful_lamp_the_1001_nights', 'fbi_paranormal_case', 'dr_jekyll_mr_hyde_strange_case_extended') GROUP BY `game_id`