MySQLI OOP or Procedure?

Hello.

Which is better to use OOP or Prodecude?
PHP: The MySQLi Extension Function Summary - Manual

What is more fast? Which use less memory etc…?

I don’t know about speed of execution of memory consumption but my personal preference is prodedural but wrapped up into my own custome database class so then if I decide to use a different database system and extension in the future, all I need do is to change the database class.

Two interfaces are provided so that you can choose the most sensible for your code. If the rest of your code is object-oriented then use the OO interface, otherwise use the procedural one. Or, both.