如何正确制作查询触发器



代码:

CREATE TRIGGER `TriggerUpdateNewsAfterChangeLikes` AFTER INSERT, UPDATE, DELETE ON `Likes`
FOR EACH ROW
BEGIN 
UPDATE `News` SET 
`CountUpLikes` = (SELECT COUNT(*) FROM `Likes` WHERE `NewsIdn` = OLD.`NewsIdn` AND `Type` = 'up'),
`CountDownLikes` = (SELECT COUNT (*) FROM `Likes` WHERE `NewsIdn` = OLD.`NewsIdn` AND `Type` = 'down'),
`CountFavorites` = (SELECT COUNT(*) FROM `Likes` WHERE `NewsIdn` = OLD.`NewsIdn` AND `IsFavorite` = 'yes');
END

当我进行查询时,在phpmyadmin中,我会出现错误:

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' UPDATE ON `Likes`
FOR EACH ROW
BEGIN 
UPDATE `News` SET 
`CountUpLikes` = (' at line 1 

请告诉我,为什么我会遇到此错误以及如何使其正确查询?

尝试这样的东西:

    CREATE TRIGGER TriggerUpdateNewsAfterChangeLikes AFTER UPDATE ON Likes
    FOR EACH ROW
    BEGIN 
    UPDATE News SET 
    CountUpLikes = (SELECT COUNT(*) FROM `Likes` WHERE `NewsIdn` = OLD.`NewsIdn` AND `Type` = 'up');
    UPDATE News SET
    CountDownLikes = (SELECT COUNT (*) FROM `Likes` WHERE `NewsIdn` = OLD.`NewsIdn` AND `Type` = 'down');
    UPDATE News SET
    CountFavorites = (SELECT COUNT(*) FROM `Likes` WHERE `NewsIdn` = OLD.`NewsIdn` AND `IsFavorite` = 'yes');
    END;

不幸的是,MySQL不允许在同一触发器上进行多个事件。

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