A useful tool to have in in your WordPress toolbelt is the ability to quickly and easily search for, find, and replace specific strings of text directly from the MySQL database. We can do this by entering SQL queries either directly or through one of those handy interface applications like phpMyAdmin, which seems like one of the most prevalent PHP applications on servers today.
Hopefully, you have some experience working directly with the database, but even if you’re new to it, the simple recipes presented in this DiW article will help you find, replace, and delete specific text content using a few simple SQL commands. This gives you incredible power to make sitewide changes to your posts, comments, or any other database table with a few simple clicks.
UPDATE wp_posts SET post_content=''
And of course keep in mind that this query may be modified as explained in the article to search for, remove, and replace any content – markup, text, special characters – in your WordPress database. For site admins and serious bloggers, this is an excellent way to speed up maintenance and get things done.
Of course, there’s probably a plugin that will do all of this for you.