如何更新觸發器中的多個表和字段？

Question

我有以下架構：SQL Fiddle。

觸發器正在更新articles.votes字段。我還需要它使用與更新articles.votes字段相同的公式更新members.points字段和成員lifetime_points字段。我怎麼做？

Answer 1

你在找？

DELIMITER $$ 
CREATE TRIGGER tg_ai_article_votes 
AFTER INSERT ON article_votes 
FOR EACH ROW 
BEGIN 
    UPDATE articles 
    SET votes = COALESCE(votes, 0) + 1 
    WHERE id = NEW.article_id; 
    UPDATE members 
    SET points = COALESCE(points, 0) + 1, 
     lifetime_points = COALESCE(lifetime_points, 0) + 1 
    WHERE id = NEW.member_id; 
END$$ 

CREATE TRIGGER tg_ad_article_votes 
AFTER DELETE ON article_votes 
FOR EACH ROW 
BEGIN 
    UPDATE articles 
    SET votes = COALESCE(votes, 0) - 1 
    WHERE id = OLD.article_id; 
    UPDATE members 
    SET points = COALESCE(points, 0) - 1, 
     lifetime_points = COALESCE(lifetime_points, 0) - 1 
    WHERE id = OLD.member_id; 
END$$ 
DELIMITER ; 

這裏是SQLFiddle演示