mysql用户自定义函数实例与部分问题解决方法_MySQL
一、查看创建函数的功能是否开启:
mysql> show variables like '%func%'; +-----------------------------------------+-------+ | Variable_name | Value | +-----------------------------------------+-------+ | log_bin_trust_function_creators | ON | +-----------------------------------------+-------+ 1 row in set (0.02 sec)
二、如果Value处值为OFF,则需将其开启。
mysql> set global log_bin_trust_function_creators=1; use app02 delimiter // mysql>DROP FUNCTION IF EXISTS `testhanshu`; CREATE FUNCTION `testhanshu`(`tustate` int) RETURNS varchar(2000) BEGIN declare oneAddr varchar(200) default ''; declare allAddr varchar(2000) default ''; DECLARE done INT DEFAULT FALSE; declare curl CURSOR for select utruename from tsys_user where ustate = tustate; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1; open curl; REPEAT FETCH curl INTO oneAddr; IF NOT done THEN set oneAddr = CONCAT(oneAddr, ';'); set allAddr = CONCAT(allAddr, oneAddr); END IF; UNTIL done END REPEAT; close curl; RETURN allAddr; END; mysql>select testhanshu(1);
在使用MySql自己定义的函数时,出现错误java.sql.SQLException: This function has none of DETERMINISTIC, NO SQL, or READS SQL DATA in its declaration and binary logging is enabled (you *might* want to use the less safe log_bin_trust_function_creators variable)
解决办法有三种:
1. 登录MySql客户端,执行: SET GLOBAL log_bin_trust_function_creators = 1;
2.在登录MySQL服务器是,在服务启动时加上 “--log-bin-trust-function-creators=1 ”参数并设置为1。
3.在my.ini(my.cnf)中的[mysqld]区段中加上 log-bin-trust-function-creators=1。
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