[wp-hackers] tags and categories combined not working: is it a bug or a feature?

[Burobjorn]

Hi,

After some trial and error and some pointers by Christine and people on 
IRC it seems that using both 1 tag and 1 category produces SQL code but 
no results. However using multiple tags and 1 category does give back 
results. This is odd as there should be a result both times. Perhaps 
this is a bug?

== what I did ==
I have a lot of posts which belong to categories. Every post belongs to 
at least 2 categories, namely a parent category and a child.

i.e.
parent category: mediaskills and awarness
child category: media-awarness

Every post has also been tagged with at least one tag and mostly with 
more than 2.

i.e.
elderly, kids, teens

Now I would like to get all posts in the category media-awarness (let's 
say the id for this is 12) with the tags 'elderly' and 'kids'. I do this 
using query url parameters:

http://mediawijsheid/?tag=ouderen+kinderen&cat=12

This results in the following query code which I dumped using
<?php global $wp_query; print_r($wp_query) ?> in the search.php template:

SELECT SQL_CALC_FOUND_ROWS wp_posts.* FROM wp_posts INNER JOIN 
wp_term_relationships ON (wp_posts.ID = wp_term_relationships.object_id) 
INNER JOIN wp_term_taxonomy ON (wp_term_relationships.term_taxonomy_id = 
wp_term_taxonomy.term_taxonomy_id) WHERE 1=1 AND 
wp_term_taxonomy.taxonomy = 'category' AND wp_term_taxonomy.term_id IN 
('12') AND wp_posts.ID IN (7, 8, 17) AND post_type IN('page', 'post') 
AND (post_status = 'publish' OR post_status = 'private') GROUP BY 
wp_posts.ID ORDER BY post_date DESC LIMIT 0, 10

And I get the results I would expect. When I want to get all posts in 
the category media-awarness (still using id 12) and just the tag 
'elderly' I get the following SQL code and no results :

SELECT SQL_CALC_FOUND_ROWS wp_posts.* FROM wp_posts INNER JOIN 
wp_term_relationships ON (wp_posts.ID = wp_term_relationships.object_id) 
INNER JOIN wp_term_taxonomy ON (wp_term_relationships.term_taxonomy_id = 
wp_term_taxonomy.term_taxonomy_id) WHERE 1=1 AND 
wp_term_taxonomy.taxonomy = 'category' AND wp_term_taxonomy.term_id IN 
('12') AND wp_term_taxonomy.taxonomy = 'post_tag' AND 
wp_term_taxonomy.term_id IN ('19') AND post_type IN('page', 'post') AND 
(post_status = 'publish' OR post_status = 'private') GROUP BY 
wp_posts.ID ORDER BY post_date DESC LIMIT 0, 10

What the heck is going on?

Any help much appreciated!

All the best,

grtz
BjornW

-- 

met vriendelijke groet,
Bjorn Wijers

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