title: Warning: mysqli_error() expects parameter 1 to be mysqli, null given in
body: <p>Warning: mysqli_error() expects parameter 1 to be mysqli, null given in error persists when am trying to upload a csv file into the database.</p>
  
  <p>below is my code snippet. I don't where i could be misfiring.</p>
  
  <pre><code>&lt;?php 
  
  class UploadFIle
  {
     function __construct()
  {
  
  }
  public function insertFile($filename,$tableName){
      global $db_mysqli_connection;
      $queryTruncate="TRUNCATE table ".$tableName;
      mysqli_query($db_mysqli_connection,$queryTruncate);
      $handle = fopen($filename, "r");
      $query='INSERT INTO '.$tableName.' VALUES ';
  
       while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) {
          $limit=sizeof($data);
          $query.='(';
          $counter=0;
          while($limit&gt;0){
              $query.="\"".$data[$counter]."\"".',';
              ++$counter;
              --$limit;
          }
  
          $query=rtrim($query,',');
  
          $query.='),';
  
       }
       $query=rtrim($query,',');
       mysqli_query($db_mysqli_connection,$query) or die(mysqli_error($connection).$query);
  
          if (mysqli_affected_rows($db_mysqli_connection)&lt;=0) {
             // echo "\nQuery execute failed: ERRNO: (" . $mysqli-&gt;errno . ") " . $mysqli-&gt;error;
              $csvMessage = "Upload Failed &lt;br/&gt;" . $db_mysqli_connection-&gt;error ;
          }else{
              $csvMessage = "Upload Successful";
          }
          return $csvMessage;
          //var_dump($mysqli);
  }
  </code></pre>
  
  <p>}</p>
  
  <p>?></p>