July 25, 2010 in Quick Fixes, Web Development by Rajendra

MySql Dump Using a PHP Script

When you need to take a backup of a large MySql database, then “mysqldump” command come most handy and does the task in few seconds. But for that we need to access the web server or database through SSH. And database access in 99% cases is not allowed from remote location for security reasons.

I found myself in such situation recently and PhpMyAdmin export feature was not working due to script timeout or memory issues. So I googled for this and after 15-20 minutes of searching I found this very useful and working small script for the job.


$User = ""; // Put New user -- CPanel user or MySQL user with All permissions is fine.
$Password = ""; // Put New Password
$DatabaseName = ""; // Put Database name
$File = ""; // Put the complete path here -- /home/user/database.sql for example
$Results = shell_exec( "mysqldump --allow-keywords --opt -u$User -p$Password $DatabaseName > $File");


Just upload the file on the web server and execute it. Do remember to specify the path of the file so that it is accessible from the web e.g. provide any path which is inside public_html or www folder on most servers.

It will take just few seconds for 300-400MB database and then you can download the file and use it as you like.

April 12, 2010 in Quick Fixes, Web Development by Rajendra

Issue of wierd characters in a dynamic PHP web page

When using special characters in UTF-8 character encoding, sometimes when you read something from mysql database then it is not displayed properly on the web page. Many of you like me may try to change the character encoding of the HTML page to ISO-8859-1, that may work sometimes but this is not the proper solution to the problem.

Irrespective of the character encoding used by MySql to store the text data, when you query something using SQL it returns the data encoded in the latin charset. This is defined in the mysql config files, as described below:

The character_set_results system variable indicates the character set in which the server returns query results to the client. This includes result data such as column values, and result metadata such as column names.

To change the character encoding to UTF8 or other, you need to use “mysql_set_charset()” mysql function in PHP. Pass the correct encoding name required and now future mysql queries will return result using new encoding.