How to Setup a PHP Script in Crontab to Clean Multiple WordPress (Database) on Same Server?

  set_time_limit(600);
  mysql_connect("localhost", "user", "password") or die(mysql_error());
                              
  function run_query($query) {
    echo $query;
    mysql_query($query) or die(mysql_error());
    echo " ***OK!*** \n";
  }                                     

  function clean_wp($db_name, $table_prefix, $skipwp = false) {
    mysql_select_db($db_name);
 
    echo "Optimising $db_name... \n";
    
    if (!$skipwp) {
      $query = "
        DELETE `a`, `b`, `c` FROM `{$table_prefix}terms` AS `a` 
        LEFT JOIN `{$table_prefix}term_taxonomy` AS `c` ON `a`.`term_id` = `c`.`term_id` 
        LEFT JOIN `{$table_prefix}term_relationships` AS `b` ON `b`.`term_taxonomy_id` = `c`.`term_taxonomy_id` 
        WHERE `c`.`taxonomy` = 'post_tag' AND `c`.`count` = 0";
  
      run_query($query);
      
      $query = "
        DELETE `a`, `b`, `c`
        FROM `{$table_prefix}posts` as `a`
        LEFT JOIN `{$table_prefix}term_relationships` as `b` ON ( `a` . `ID` = `b` . `object_id` )
        LEFT JOIN `{$table_prefix}postmeta` as `c` ON ( `a` . `ID` = `c` . `post_id` )
        WHERE `a` . `post_type` = 'revision' 
      ";
  
      run_query($query);
        
      $query = "
        DELETE FROM `{$table_prefix}commentmeta`
        WHERE `comment_id` NOT IN (
          SELECT `comment_id`
          FROM `{$table_prefix}comments` 
        )
      ";
        
      run_query($query);
  
      $query = "
        DELETE FROM `{$table_prefix}commentmeta` 
        WHERE `meta_key` LIKE \"%akismet%\"
      ";
        
      run_query($query);  
  
      $query = "
        DELETE FROM `{$table_prefix}comments` 
        WHERE `comment_approved` <> 1
      ";
      
      run_query($query);
      
      $query = "
        DELETE FROM `{$table_prefix}posts` 
        WHERE `post_type` = \"revision\"
      ";
  
      run_query($query);
    }
 
    $alletabellen = mysql_query("SHOW TABLES");
 
    while($tabel = mysql_fetch_assoc($alletabellen))
    {
        foreach ($tabel as $db => $tabelnaam) 
        {
            $query = "REPAIR TABLE `$tabelnaam`";
            run_query($query);
            
            $query = "OPTIMIZE TABLE `$tabelnaam`";
            run_query($query);
        }
    }
    
    echo " --- Done!!! ---";
  }