There might be an easier way out there, but one way to do it is to go into your database and find the table wp_categories (it might be named something else similar depending on your tables’ prefixes).
There, note the cat_ID number for the category you want to move the posts FROM as well as the cat_ID for the category you want to move the posts TO.
Then go to table wp_post2cat and in the field named “category_id” update every instance of a FROM category number to the number of the TO category. If you know a little MySQL it should take a couple of seconds to do.
There you’ll see the fields “rel_id,” “post_id,” and “category_id.”
I have no idea about MySQL. I hope “There might be an easier way out there”.
Well easy is a matter of taste. In the Dashboard/Manage/Posts you can click the edit tag of any post, unmark the original category where the post is published, mark any category (ies ) and republish ( Save ).
This would be tedious if you are moving many posts, but doesn’t require any MySQL knowledge.
Very quick MySQL method:
UPDATE wp_post2cat SET category_id = '2' WHERE category_id = '1';
Change the “wp_” prefix (wp_post2cat) to the one set for $table_prefix in your wp-config.php.
Alter ‘2’ from SET category_id = '2' to the numeric category ID you want to change *to*.
Alter ‘1’ from WHERE category_id = 1 to the numeric category ID you want to change *from*.
Forgot to note that WordPress “caches” the post count within a category. To reset this, just resave one of the posts that was moved to the new category.
I don’t dare to go into MySQL and fix the problem. I thougth it would be a plugin or any other solution to solve my problem. Now, I don’t know what to do.
If you are using 1.5.2 you can use Batch categories
I am using 1.5.1, could I use this plugin?
I am not sure. I think there are some security issues with 1.5.1 so it may be wise to upgrade to 1.5.2 anyway. (I think there is a post somewhere that batch categories does not work with 2.0).
http://static.wordpress.org/archive/ for older versions.
