触发器在mysql中乘以“基于触发器的列”

本文介绍了触发器在mysql中乘以“基于触发器的列”的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 29岁程序员，3月因学历无情被辞！ 我以前问过这个问题，我想详细说明。I have asked this question before and I want to elaborate it. 触发器连接多个表Triggers to connect multiple tables我有以下触发器（类似我之前问过的那种）：I have the following trigger (kind of like the one I asked before):CREATE TRIGGER trigger_test1BEFORE INSERT ON test1FOR EACH ROW SET NEW.OriginIndex = (SELECT index1 FROM cities WHERE city = NEW.Origin), NEW.DestinationIndex = (SELECT index1 FROM cities WHERE city =NEW.Destination);这部分效果很好。现在我想乘以OriginIndex和DestinationIndex并将其存储在另一列（我们说乘法）。This part works well. Now I want to multiply OriginIndex and DestinationIndex and store it in another column (let's say 'Multiplication').我这样做：CREATE TRIGGER trigger_test1BEFORE INSERT ON test1FOR EACH ROW SET NEW.OriginIndex = (SELECT index1 FROM cities WHERE city = NEW.Origin), NEW.DestinationIndex = (SELECT index1 FROM cities WHERE city =NEW.Destination), NEW.Multiplication = (SELECT NEW.OriginIndex*NEW.DestinationIndex);这会产生错误'此版本的MySQL尚不支持'时间和事件。This gives an error 'This version of MySQL doesn't yet support 'multiple triggers with the same action time and event for one table''.我应该如何处理这个问题？How am I supposed to approach this problem?推荐答案我认为您可以使用DELIMITER //CREATE TRIGGER trigger_test1BEFORE INSERT ON test1BEGINFOR EACH ROWSET NEW.OriginIndex = (SELECT index1 FROM cities WHERE city = NEW.Origin);SET NEW.DestinationIndex = (SELECT index1 FROM cities WHERE city =NEW.Destination);SET NEW.Multiplication = (NEW.OriginIndex*NEW.DestinationIndex);END//我希望有帮助。 这篇关于触发器在mysql中乘以“基于触发器的列”的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！ 上岸，阿里云！