Wordpress provide a great feature of maintaining Revisions or History of a Post. Since WordPress 2.6, whenever you create a post in WordPress, it keeps on maintaining history.
This feature might be very useful in a multi-author blog where more then one user is contributing in a post, but it may simply not required when you are the only one contributing in that post. Not only does WordPress create and stores all the past revision automatically every 10 minutes or so, it causes your server MySQL database to be bloated with unwanted data. Within a few months, your ‘wp_posts’ table will be filled up, clustered, and the post ID will be gigantic. Worst case scenario when you backup your MySQL is to have a 50MB database, too big for uploading in case of server failure.
So how to disable automatic revision history creation in wordpress? Simply follow these steps:
Disable WordPress Revision History
Open your wp-config.php file which will be in wordpress root installation directory.
Paste following line anywhere in that file.
This will simply disable Auto Revision History creation from wordpress.
Delete previous Revision Histories in WordPress
Using above technique will not delete your previous saved post revisions, to remove previous post revision permanently, run this query using the PHPMyAdmin:
DELETEFROM wp_posts WHERE post_type = “revision”;
Now all post revisions related records should have been purged from your SQL database and all revision history should have been deleted.