Tips to remove unwanted post revision and disable post revision features on WordPress:
1. SQL command to delete post revisions
I would assume you know how to login to your phpMyAdmin and know how to execute SQL command. So, simply run this SQL command and all stored post revisions will be deleted.
DELETE FROM wp_posts WHERE post_type = “revision”;
2. Use Delete Post Revision WordPress plugin
Delete Revision is a simple wordpress plugin that remove all revision post within few click. This wordpress plugin also automatically search for post revision on your wordpress database by pressing the Check Redundant Revision button.
Download Delete Revision
3. Disable Post Revision features on WordPress
You can turn off post revision feature by go to your wp-config.php and add define(’WP_POST_REVISIONS’, false); before the closing ?> tag
How to Turn off WordPress Post Revisions:
Login via an ftp client to the folder containing your WordPress site
Copy the wp-config.php file to your desktop
Using a text editor ( example :notepad), open the wp-config.php file
Before the closing ?> tag, add the following line of code:
Save the file and upload it to your server, overwriting the old file
So, the above revision posts trick streamline your wordpress database, making it smaller in the query post process.
NOTE: Do this with care. If you are not sure what you are doing, make sure to at least create a backup of the database first or even better, ask a professional to help you. Remember, both the SQL command and delete revision plugin will delete all your post revisions, and you are not allow to choose which revesion to be deleted. So, please make sure you won’t regret after delete them!