MySQL integer overflow warning script

This PHP script will check all MySQL tables and warn you if any integer fields with an AUTO_INCREMENT setting are approaching the limit of that field's datatype.

When the limit for a field size is reached future INSERT operations will fail (generating an ERROR 1467: Failed to read auto-increment value from storage engine) resulting in an annoyed user. Set up a cronjob to run this script regularly and email the results to receive a warning in time to increase the limit or take other action before any damage is done.

// Connect to server and select database Update with your credentials

// Warn me if this % of the datatype's limit is breached

// Limits as specified
  $Limits=['tinyint'            =>  127,
           'tinyint unsigned'   =>  255,
           'smallint'           =>  32767,
           'smallint unsigned'  =>  65535,
           'mediumint'          =>  8388607,
           'mediumint unsigned' =>  16777215,
           'int'                =>  2147483647,
           'int unsigned'       =>  4294967295,
           'bigint'             =>  9223372036854775807,
           'bigint unsigned'    =>  18446744073709551615];

  $Tables=mysqli_query($Link,'show tables') or exit('could not list tables');


      $Columns=mysqli_query($Link,'show columns from '.$Table[0].' where Extra="auto_increment"');
// Integer types will be in the format /(tiny|small|medium|big)?int\(\d+\) (unsigned)?/

          $Max=mysqli_query($Link,'select Max('.$Column['Field'].') as Max from '.$Table[0]);


              $Text.='** INTEGER LIMIT APPROACHING! **'."\n";
              $Text.='Table    '.$Table[0]."\n";
              $Text.='Field    '.$Column['Field']."\n";
              $Text.='Datatype '.$Column['Type']."\n";
              $Text.='Current  '.$Data['Max']."\n";
              $Text.='Limit    '.$Limits[$DataType]."\n";
              $Text.='%        '.$Percent."\n\n";
        } // Column block
    } // Table loop

      $Text='Datatype limits ok';

  echo $Text;


Yes, a good coder should be able to choose realistic datatypes for the data they will be storing allowing for room to grow, but I don't like to leave things to chance!