PHP mySQL Database backup

There are times when you need to get an SQL dump of a database but you don’t have access to management tools AND system(), exec() and passthru() commands are disabled. This script from David Walsh will do the trick:

<?php
/**
 * Thaks to David Walsh (http://davidwalsh.name/backup-mysql-database-php)
 */

backup_tables('localhost', 'root', '', 'bvcb_forms');

/* backup the db OR just a table */

function backup_tables($host, $user, $pass, $name, $tables = '*') {

    $return = '';

    $link = mysql_connect($host, $user, $pass);
    mysql_select_db($name, $link);

    //get all of the tables
    if ($tables == '*') {
	$tables = array();
	$result = mysql_query('SHOW TABLES');
	while ($row = mysql_fetch_row($result)) {
	    $tables[] = $row[0];
	}
    } else {
	$tables = is_array($tables) ? $tables : explode(',', $tables);
    }

    //cycle through
    foreach ($tables as $table) {
	$result = mysql_query('SELECT * FROM ' . $table);
	$num_fields = mysql_num_fields($result);

	$return.= 'DROP TABLE ' . $table . ';';
	$row2 = mysql_fetch_row(mysql_query('SHOW CREATE TABLE ' . $table));
	$return.= "\n\n" . $row2[1] . ";\n\n";

	for ($i = 0; $i < $num_fields; $i++) {
	    while ($row = mysql_fetch_row($result)) {
		$return.= 'INSERT INTO ' . $table . ' VALUES(';
		for ($j = 0; $j < $num_fields; $j++) {
		    $row[$j] = addslashes($row[$j]);
		    $row[$j] = preg_replace("/\n/", "/\\n/", $row[$j]);
		    if (isset($row[$j])) {
			$return.= '"' . $row[$j] . '"';
		    } else {
			$return.= '""';
		    }
		    if ($j < ($num_fields - 1)) {
			$return.= ',';
		    }
		}
		$return.= ");\n";
	    }
	}
	$return.="\n\n\n";
    }

    //save file
    $handle = fopen('db-backup-' . time() . '-' . (md5(implode(',', $tables))) . '.sql', 'w+');
    fwrite($handle, $return);
    fclose($handle);
}
?>