How to put mysql inside a php function?

Question

I have problem about putting mysql into a function showMsg(). The mysql is working fine if it is not wrapped by function showMsg(), but when I wrap it with function showMsg(

Answer 1

1. Never use global.
   Pass $connection into your function as an argument.

2. Logic and representation should be separated.
   Read about MVC: here or here.

3. Global variables are evil, never use it. If someone suggests it - ignore all their answers.