ERROR 1044 (42000): Access denied for user 'root'@'localhost'

从供应商那边接手一个MySQL数据库（数据库版本为5.7.21 MySQL Community Server (GPL)），在创建账号时遇到了“ERROR 1044 (42000): Access denied for user 'root'@'localhost' to database xxx”错误，如下所示

 

 

mysql> grant all on xxx.* to xxx@'192.168.%' identified by 'xxx';

ERROR 1044 (42000): Access denied for user 'root'@'localhost' to database 'xxxx'

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