Обновлять одну таблицу с выборкой из другой просто. Вот реально работающий случай в триггере "user.tr_user_after_update": UPDATE user_prize_block,prize_fund SET user_prize_block.block="U" WHERE user_prize_block.fund=prize_fund.id AND prize_fund.block_same_ip!="N" AND prize_fund.block_same_ip_monitor_ip_changes="Y" AND prize_fund.active="Y" AND user_prize_block.id=NEW.id AND user_prize_block.block="N" Ещё по теме с LEFT JOIN читать тут: https://stackoverflow.com/questions/1262786/mysql-update-query-based-on-select-query UPD. Ещё более ранний пример с LEFT JOIN'ом, в mySQL-функции "refresh_company_active_banner". UPDATE company LEFT JOIN banner ON banner.company=company.id AND banner.active="Y" AND (banner.active_campaign="Y" OR (slimit="D" AND start<=CURRENT_DATE AND expire>=DATE_SUB(CURRENT_DATE, INTERVAL 3 MONTH))) SET has_active_banner_campaign=IF(banner.id IS NULL,"N","Y") WHERE IF(comp_id>0 AND comp_id IS NOT NULL, company.id=comp_id, 1); ———————————— UPD. Вот ещё удаление из одной таблицы, при выборке из двух: DELETE category_favorit_audit FROM category_favorit_audit,mark WHERE category_favorit_audit.mark=mark.id AND mark.category=698 ———————————— This document has been copied from FAVOR.com.ua (https://favor.com.ua/en/blogs/29157.html). All rights reserved by author of the material. In case of re-publication, the link to the source of the material is strongly required! Document date: November 9, 2017