Every time you update your posts or pages wordpress will automatically backup the last version of the posts. This feature can be very helpful when you want to go back in time and change your posts to the past version, but I find it clogging up the database as each update will add an new line to the database. Over time it can add up and I don't really need this anyways.

To remove this Post Revisions.

First open up wp-config.php and add the line below...
define('WP_POST_REVISIONS', false);

To delete and remove all existing post revisions entries and rows from WordPress database Posts table, simply login to MySQL command-line interface, phpMyAdmin, SQLyog or other MySQL GUI tools. Select the appropriate WordPress database (if you have more than one databases on the same server), and then issue the following command (it's also recommended to backup the database before performing the deletion SQL statements):

Click the Query Window icon on the top left corner of your phpmyadmin. See image below. Make sure you select the correct database first. When you click the Query Window icon, you should get a pop up, just past in the code DELETE FROM wp_posts WHERE post_type = "revision"; and clcik GO. Again make sure you back up first before doing this.


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