In my PHP codes, I always have this problem that I can not use include somewhere!

For e.g. I’m using MySQL to connect to my database and I made a global.php to include & connect to my database and use it for all other PHP files.

But somewhere I keep getting the error:

Fatal error: Cannot redeclare connect() (previously declared in C:\xampp\htdocs\mypm\functions\global.php:4) in C:\xampp\htdocs\mypm\functions\global.php on line 7

I can not include or use some files that uses global.php in other PHP files!

Any suggestions? Thanks