Answers for "mysqli_fetch_assoc() expects parameter 1 to be mysqli_result, boolean given"

Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, string given in

mysqli_fetch_array($result)

Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, string given in

mysqli_fetch_array($query)

mysqli_fetch_assoc() expects parameter 1 to be mysqli_result, bool given in

// Use double quotes for queries, or varibales can't be interpretated
$sql = "SELECT * FROM $usertable WHERE PartNumber = $partid";