Object Oriented Style

  $stmt = $maindb->prepare("DELETE FROM some_table WHERE email_address = ? ");
  $stmt->bind_param("s", $MyColumn1 );
  $MyColumn1 = "abc";
  $stmt->execute();
  $stmt->close();

Procedural Style

  mysqli_query($dblink, "DELETE FROM some_table WHERE email_address = '$email'");

Delete old records by date

  mysqli_query($dblink, "DELETE FROM messages_sent WHERE created_date < DATE_SUB(NOW(), INTERVAL 30 DAY)");

  //Also:
  //INTERVAL 1 MONTH
  //INTERVAL 1 HOUR
  //etc

Delete table

Truncate is the fastest method to delete all data in a table as the table is dropped and re-creaed.

  mysqli_query($dblink, "TRUNCATE TABLE all_songs");