When using the MySQL database, sometimes the MySQL function cannot be created. The following will teach you a method to solve the problem of MySQL function cannot be created for your reference. Hope it helps everyone.
Case 1:
Currently in the project, an error occurs when executing the function that creates mysql.
The error message for the mysql creation function is as follows:
Error Code: 1227 . Access denied; you need (at least one of) the SUPER privilege(s) for this operation
First check whether the creation function is enabled. The SQL to check whether the creation function is enabled is as follows:
-- 查看是否开启创建函数的功能 show variables like '%func%'; -- 开启创建函数的功能 set global log_bin_trust_function_creators = 1;
After executing the SQL, you find that it has been enabled. Check whether your SQL is written incorrectly (because the SQL was given by others, it will be fine in other people's environments, but it may be possible in your own environment).
Suddenly discovered that there was indeed a problem with SQL. Because the SQL he created had a designated user, the problem occurred. The following is his SQL:
DROP FUNCTION IF EXISTS `nextval`; DELIMITER ;; CREATE DEFINER=`devop`@`%` FUNCTION `nextval`(`seq_name` VARCHAR(50)) RETURNS varchar(20) CHARSET utf8 BEGIN DECLARE seq_max BIGINT(20); UPDATE sequenceconftable SET `max` = `max` + NEXT WHERE NAME = seq_name; SELECT `max` INTO seq_max FROM sequenceconftable WHERE NAME = seq_name ; RETURN seq_max; END ;; DELIMITER ;
Due to the CREATE_FUNCTION specification, it can be found that it is DEFINER This parameter can specify the database user, but your own library is not this user, so it causes problems.
The problem has been solved.
-EOF-
Case 2:
When creating a user-defined function in MySQL, the following error was reported:
ERROR 1418 (HY000): 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)
This is because there is a security The parameter is not turned on. The default value of log_bin_trust_function_creators is 0, which does not allow function synchronization. If this parameter is turned on, the creation will be successful.
mysql> show variables like '%fun%'; +---------------------------------+-------+ | Variable_name | Value | +---------------------------------+-------+ | log_bin_trust_function_creators | ON | +---------------------------------+-------+ 1 row in set (0.00 sec) mysql> set global log_bin_trust_function_creators=1; Query OK, 0 rows affected (0.00 sec) mysql> show variables like '%fun%'; +---------------------------------+-------+ | Variable_name | Value | +---------------------------------+-------+ | log_bin_trust_function_creators | ON | +---------------------------------+-------+ 1 row in set (0.00 sec)
If this parameter is enabled on the master, remember to enable this parameter on the slave side as well (the slave needs to be stopped and then restarted), otherwise creating a function on the master will cause the replication to be interrupted.
Case 3:
Error Code: 1418
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) (0 ms taken)
Analysis:
According to the system prompts, the cause of this error may be a security For settings configuration, check the manual. The log_bin_trust_function_creators parameter defaults to 0, which does not allow synchronization of functions. Generally, when we configure the replica, we forget to pay attention to this parameter. In this way, after the master updates the function, the slave will report an error, and then the slave stopped.
Processing process:
Log in to the mysql database
> set global log_bin_trust_function_creators = 1; > start slave;
Trace the startup log of mysql, the slave runs normally, and the problem is solved.
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