Title: category JOIN question
Last modified: August 18, 2016

---

# category JOIN question

 *  [youngmicroserf](https://wordpress.org/support/users/youngmicroserf/)
 * (@youngmicroserf)
 * [19 years, 2 months ago](https://wordpress.org/support/topic/category-join-question/)
 * Hi,
 * I’ve imported a big multiblog installation from Movable Type into WP with a hack
   so that the MT blog name would become a WP category. Thus there are now 4 primary
   categories that contain all posts of the respective previous MT blogs. And there
   are all the other categories. The problem I am facing is that some blogs are 
   having some overlapping categories apart from the 4 main ones. So, assuming category
   5 is “foo”, some posts from category 1 (first blog) and some from category 2 (
   second blog) have imported into the same “foo” category.
 * Is there a way to get, on, say, the “2” blog-category page a sidebar that links
   to a “foo” category that only contains links that are in both the category listed*
   and* the category whose page is being displayed?
 * In a way… show me all categories in category 2 to which there was also another
   category assigned. And then, if clicked, a category archive only containing those
   posts that are in both categories?
 * Is this possible using a standard WP function?
    Or do I have to use a custom 
   $WPDB->query to do that? Or is it actually necessary to reassign categories hiearchically(
   so there would be two “foo” categories, one in the parent 1 and one in the parent
   2).
 * Thanks for any help!
 * yms

The topic ‘category JOIN question’ is closed to new replies.

## Tags

 * [categories](https://wordpress.org/support/topic-tag/categories/)
 * [Import](https://wordpress.org/support/topic-tag/import/)

 * In: [Developing with WordPress](https://wordpress.org/support/forum/wp-advanced/)
 * 0 replies
 * 1 participant
 * Last reply from: [youngmicroserf](https://wordpress.org/support/users/youngmicroserf/)
 * Last activity: [19 years, 2 months ago](https://wordpress.org/support/topic/category-join-question/)
 * Status: not resolved

## Topics

### Topics with no replies

### Non-support topics

### Resolved topics

### Unresolved topics

### All topics