How to Change Joomla Database Prefix

1...Make change.php file with following code and changes according to your new prefix:

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<?php
$db_server = "localhost" ;
$db_name = "type dabase name here";
$db_username = "type dabase username here";
$db_password = "type database password here";

$old_pattern = "jos_" ;
$new_pattern = "type new prefix here_" ;

$session_id = mysql_connect( $db_server, $db_username, $db_password);
if (!$session_id) { die('Connection Failed: ' . mysql_error());}

$query = "SHOW TABLES FROM `" . $db_name . "`" . " LIKE '%" . $old_pattern . "%'";
$result = mysql_query ( $query, $session_id );
if (!$result) {die("Query Failed: " . mysql_error( $session_id ));}

while ( $row = mysql_fetch_array ($result) ) {
$old_table_name = $row[0];
$new_table_name = str_replace ($old_pattern, $new_pattern, $old_table_name);
$query = "RENAME TABLE `".$db_name."`.`".$old_table_name."`"." TO `".$db_name."`.`".$new_table_name."`";
if (mysql_query ( $query, $session_id )) {
echo "$old_table_name renamed to $new_table_name <br />";
} else {
echo "Error: $old_table_name not renamed" . mysql_error( $session_id ) . "<br />";
}
}
mysql_close( $session_id );
?>
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2...Open this file into the browser

3...Go to configuration.php file and change
     var $dbprefix = 'new prefix_';



You are done.......:)