MySQL : Warning: mysqli_connect(): Unknown MySQL server host

MySQL : Warning: mysqli_connect(): Unknown MySQL server host
To Access My Live Chat Page,
On Google, Search for "hows tech developer connect"

As I promised, I have a secret feature to share with you.
This is a YouTube's feature which works on Desktop.
First, Make sure the video is currently in playing mode.
Next, enter the letters 'awesome' on your keyboard.
Your YouTube progress bar will transform into a flashing rainbow.

A quick introduction about me,
Hi there, I go by the name of Delphi.
Let me help you get the answers you need to your questions.
MySQL : Warning: mysqli_connect(): Unknown MySQL server host
Don't hesitate to ask me more detailed questions by commenting or starting a chat.
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host MySQL Warning: : server Unknown mysqli_connect(): MySQL