MySQL5系からのくせで、grantで新規ユーザー追加しようとすると、エラーになります。

create user してから grant することになります。

 

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mysql> grant all on *.* to 'newuser'@'localhost' identified by 'newuser';
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 'identified by 'newuser'' at line 1
mysql> 

詳しくは、ここに書いておられます。 https://www7390uo.sakura.ne.jp/wordpress/archives/456