I have been working on a database with large and expanding database in MariaDB. The database is accessed by a PHP application.

I set the DB character set and collation to utf8mb4 and utf8mb4\_unicode\_ci

But not all my tables has text (varchar, text etc.) columns. Some tables holds only relations, thus all columns are number types (int, bigint etc) or date/time etc. additionally but not text types.

In tables, where I only keep numbers, do I need to keep the unicode multi-byte character set/collation or I can select something else?

Most importantly does this **affect the query performance**?