Warning: mysqli_query() expects parameter 1 to be mysqli, null given [duplicate]

Answer 1

$adConn is in the global scope and you cannot access it from the function, if you change $adConn to $GLOBALS['adConn'] it should work.

Answer 2

Because $adConn is declared outside of the function is not in scope. That means you do not have access to it inside the function. To have access to it you need to pass it as aparameter of the function.

 function GetGamesCount($wID, $adConn){