<?php
$database_host = 'localhost'; // Database hostname
$database_user = 'root'; // Database username
$database_password = ''; // Database password
$database_name = 'myjoomla'; // Database name
$new_table_prefix = 'zkl_'; // New table prefix
$old_table_prefix = 'jos_'; // Old table prefix (optional)
$test = false; // Test-run (true or false)
// NO NEED TO EDIT BELOW THIS LINE
// Login to the database server
$db = mysql_connect($database_host, $database_user, $database_password) or die('MySQL connect failed');
// Connect to the database
mysql_select_db($database_name) or die('Failed to select database');
// Get a listing of all tables
$query = "SHOW TABLES";
$result = mysql_query($query) or die('SHOW TABLES failed');
// Loop through all tables
while($row = mysql_fetch_array($result)) {
     $old_table = $row[0];
// Preliminary check: Is the old table prefix correct?
     if(!empty($old_table_prefix) && !preg_match('/^'.$old_table_prefix.'/', $old_table)) {
          echo "Table $old_table does not match prefix $old_table_prefix<br/>\n";
          continue;
     }
// Preliminary check: Is the old table prefix the same as the new one?
     if(preg_match('/^'.$new_table_prefix.'/', $old_table)) {
          echo "Table $old_table already done<br/>\n";
          continue;
     }
// Construct the new table prefix
     if(!empty($old_table_prefix)) {
          $new_table = preg_replace('/^'.$old_table_prefix.'/', $new_table_prefix, $old_table);
     } else {
          $new_table = $new_table_prefix.$old_table;
     }
// Rename the actual table
     echo "Renaming $old_table to $new_table<br/>\n";
     $query = "RENAME TABLE `$old_table` TO `$new_table`";
     mysql_query($query);
}