MYSQL语法定界符和语法错误

Question

我尝试修复以下语法错误，但在这里看不到到底是什么错误：

DELIMITER =
CREATE TRIGGER trigs BEFORE UPDATE ON autoinc 
FOR EACH ROW BEGIN 
DECLARE num_rows INTEGER; 
SELECT (*) INTO num_rows FROM autoinc;
IF num_rows >=3 THEN 
DELETE FROM autoinc LIMIT 1; 
END IF; 
END=
DELIMITER ;

错误是：

ERROR 1064 (42000): 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 '*) INTO num_rows FROM autoinc; IF num_rows >' at line 4

 ERROR 1064 (42000): 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 '3 THEN 

能帮我解决这个问题吗？

Answer 1

正如评论中已经提到的：

SELECT (*) AS num_rows ...

本来应该是

SELECT COUNT(*) AS num_rows ...

和

IF num_rows >=3 THEN 

如您定义的=分隔符。

使用代码中没有的定界符，例如：

DELIMITER //

有了这两个更改，事情应该可以正常工作而不会出现语法错误