Question

这是我的代码：

triggerBuilder.append("DROP TRIGGER IF EXISTS `insert_associated_inquiry`; ");
triggerBuilder.append(" DELIMITER %% ");

triggerBuilder.append(" CREATE TRIGGER insert_associated_inquiry BEFORE UPDATE ON inquiry ");
triggerBuilder.append(" FOR EACH ROW Begin ");    

triggerBuilder.append(" insert into associated_inquiries(inquiry_id , subject , content , inquiry_date , preferred_date ) " );
triggerBuilder.append("values");
        triggerBuilder.append(" ( " );
            triggerBuilder.append(" OLD.id , ");
            triggerBuilder.append(" OLD.subject , " );
            triggerBuilder.append(" OLD.content , " );
            triggerBuilder.append(" OLD.created_on , " );
            triggerBuilder.append(" OLD.preffered_date " );
        triggerBuilder.append(" ) ; ");

triggerBuilder.append(" END %% ");

triggerBuilder.append(" DELIMITER ; ");

con.createStatement().execute(triggerBuilder.toString());

这就是抛出的错误：

 com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: 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 'DELIMITER %%  CREATE TRIGGER insert_associated_inquiry 
 BEFORE UPDATE ON inquiry ' at line 1

这个错误的原因和解决方案可能是什么。求助。谢谢。

Answer 1

不要在JDBC和MySQL中使用分隔符。分隔符仅由MySQL控制台使用，以便它可以判断您输入的触发器，存储过程等何时结束。在JDBC中，将整个SQL字符串放在一起，然后将其发送到数据库。因为您可以控制SQL何时被发送到数据库，所以不需要使用分隔符。

我从代码中删除了两个DELIMITER行并使用了%%分隔符，并将DROP TRIGGER命令分别发送到数据库。我留下的代码如下：

con.createStatement().execute("DROP TRIGGER IF EXISTS `insert_associated_inquiry`");

triggerBuilder.append(" CREATE TRIGGER insert_associated_inquiry BEFORE UPDATE ON inquiry ");
triggerBuilder.append(" FOR EACH ROW Begin ");    

triggerBuilder.append(" insert into associated_inquiries(inquiry_id , subject , content , inquiry_date , preferred_date ) " );
triggerBuilder.append("values");
        triggerBuilder.append(" ( " );
            triggerBuilder.append(" OLD.id , ");
            triggerBuilder.append(" OLD.subject , " );
            triggerBuilder.append(" OLD.content , " );
            triggerBuilder.append(" OLD.created_on , " );
            triggerBuilder.append(" OLD.preffered_date " );
        triggerBuilder.append(" ) ; ");

triggerBuilder.append(" END ");

con.createStatement().execute(triggerBuilder.toString());

此代码似乎有效，因为无论触发器是否已存在，我都可以无错误地运行此代码。如果先前没有触发器，则会创建它。

Answer 2

原因是因为“分隔符”不是mysql标准的一部分，只需删除分隔符并且你的代码应该可以工作。

在mysql5.5上通过JDBC创建触发器时出错

2 个答案: