1055. Query Error 1055: Expression #3 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'newprofil.blog_post.datetime' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by Query: SELECT COUNT(*) AS `count`, EXTRACT(YEAR_MONTH FROM `datetime`) AS `timeline`, EXTRACT(MONTH FROM `datetime`) AS `month`, EXTRACT(YEAR FROM `datetime`) AS `year`, `blog_id` FROM `blog_post` WHERE `status` = 'published' AND `blog_id` = '1' GROUP BY EXTRACT(YEAR_MONTH FROM `datetime`) ORDER BY `timeline` DESC