PHP: mysqli_connect(): The server requested authentication method unknown to the client [caching_sha2_password]
if you have these errors in your log file: It means that the server’s default authentication plugin is different from your client’s. So you have to change the user’s default authentication plugin by this command:
Change the Character Set & Collation of a table
To change the Character Set and Collation of a field of a table you have to use this query: if the table contains data, you have to update that data as follow: