mysql触发器存储的触发器已被调用存储触发器的语句使用?mysql

我想设置一个触发器，以便在更新时预测字段为= 3，然后触发器将值更改为4并将其保存在数据库中。触发器在下面。

由于某些原因，我总是收到错误消息：

#1442 - Can't update table 'tzanalytic_forecast_cached' in stored function/trigger because it is already used by statement which invoked this stored function/trigger. 这样设置正确吗？

delimiter $$ CREATE TRIGGER no_BoW BEFORE UPDATE ON t FOR EACH ROW BEGIN set @prediction = new.prediction; UPDATE t SET t.prediction = (SELECT IF(@prediction = '3', '4', @prediction)) WHERE t.event_id = new.event_id AND t.price_tier = new.price_tier; END; $$ delimiter ;