When you edit wordpress posts it automatically creates revision of the post. This is useful if you wanted to rollback to a previous version of the post.
But a problem with this is it creates a record in database each time. This means it increases your database size. This won’t be a much issue for a small site with few posts. But when you have more posts & if you edit posts very often it will affect a lot for your site in the long run. Sometimes this will increase your site loading time & make the site to perform slowly.
Best thing is to delete the revisions often. You can do this by running a simple mysql query. This is the query for it,
DELETE a,b,c FROM wp_posts a LEFT JOIN wp_term_relationships b ON (a.ID = b.object_id) LEFT JOIN wp_postmeta c ON (a.ID = c.post_id) WHERE a.post_type = 'revision'
This will delete all the revisions as well as the post meta & term relationship records related to them.
If you wish to turn off creating revisions add following code to wp-config.php
define('WP_POST_REVISIONS', false );
Instead turn off revisions if you wish to limit the number of revision created per post, add following code to wp-config.php
define('WP_POST_REVISIONS', 3);
You can modify the number 3 to any number you like. WordPress will keep only that amount of revisions per a post.
If you are not familiar with sql & php there are many plugins that you can use to manage revisions. Here is a better one.
