mysql 如果不存在则创建用户
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mysql create user if not exists
提问by sweb
I have a query to check mysql users list for create new user.
我有一个查询来检查 mysql 用户列表以创建新用户。
IF (SELECT EXISTS(SELECT 1 FROM `mysql`.`user` WHERE `user` = '{{ title }}')) = 0 THEN
CREATE USER '{{ title }}'@'localhost' IDENTIFIED BY '{{ password }}'
END IF;
But i get this error:
但我收到此错误：
ERROR 1064 (42000) at line 3: 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 'IF (SELECT EXISTS(SELECT 1 FROM `mysql`.`user` WHERE `user` = 'cms_localhost')) = 0 ' at line 1
回答by Ascherer
In 5.7.6 and above, you should be able to use CREATE USER
在 5.7.6 及以上版本中，您应该可以使用 CREATE USER
CREATE USER IF NOT EXISTS 'user'@'localhost' IDENTIFIED BY 'password';
Note that the 5.7.6 method doesn't actually grant any permissions.
请注意，5.7.6 方法实际上并未授予任何权限。
If you aren't using a version which has this capability (something below 5.7.6), you can do the following:
如果您没有使用具有此功能的版本（低于 5.7.6），您可以执行以下操作：
GRANT ALL ON `database`.* TO 'user'@'localhost' IDENTIFIED BY 'password';
This will create the user if it doesn't exist
如果用户不存在，这将创建用户
Note, if you are on MySQL 8, the GRANT ALLmethod will not create a user.
请注意，如果您使用的是 MySQL 8，则该GRANT ALL方法不会创建用户。
回答by ingocnito
I use
我用
SELECT EXISTS (SELECT DISTINCT userFROM mysql.userWHERE user= "username") as is_user
SELECT EXISTS（SELECT DISTINCT userFROM mysql。userWHERE user= “用户名”）作为is_user
should return 1 if exists or 0 if it does not
如果存在则返回 1，否则返回 0
