I've have two sql queries which I'm trying to combine
The first:
SELECT * FROM wp_posts
JOIN wp_postmeta on (post_id=ID)
WHERE meta_key = "packageID" and meta_value = 1
ORDER BY post_date limit 50
Joins the wordpress wp_post table to the wp_postmeta and gets all the posts meeting with packageID = 1 (I think it might be an inelegant way of doing it but it works)
The second
SELECT * FROM wp_postmeta
JOIN wp_posts ON (meta_value=ID)
WHERE post_id = 2110
AND meta_key = '_thumbnail_id'
again joins the wp_post table to the wp_postmeta table, so for the post with the id 2110 it successfully gets the thumbnail for that posts. NB 2110 is just an example of an id
In Wordpress a thumbnail is a kind of post. So in this example the text which constitutes post 2110 is a associated with post 2115 - the latter being the thumbnail
What I'm trying to do is get the list as in the first query but also get thumbnails associated with each post
I think I need two joins but I can't see how to do it (being an sql beginner)
NB this will be in a script outside Wordpress so I can't use Wordpress's built-in functions
try with the following code
SELECT * FROM wp_posts wp JOIN wp_postmeta wm on (wp.post_id=wm.ID) WHERE wp.meta_key = "packageID" and wp.meta_value = 1 ORDER BY wp.post_date limit 50;
use proper alias and try it.
Try using the post_type column. The attachments have a post_type of 'attachment'. I can further explain if needed.
Also the post to which the thumbnail is attached to will be in the column post_parent.
global $wpdb;
$query7 = "SELECT distinct wp_postmeta.meta_value, wp_postmeta.meta_key, wp_posts.ID
FROM wp_posts INNER JOIN wp_postmeta ON (wp_posts.ID = wp_postmeta.post_id)
INNER JOIN wp_postmeta AS mt1 ON (wp_posts.ID = mt1.post_id)
WHERE wp_posts.ID = wp_postmeta.post_id
AND wp_posts.post_status = 'publish'
AND wp_postmeta.meta_key = 'packageID'
AND wp_postmeta.meta_value = 1
AND (mt1.meta_key LIKE '_thumbnail_id')
$output = $wpdb->get_results( $query7 );
Use join with different aliases when joining same table more than once.
Hope this helps.
You can try this one,if there are more than one thumbnails for the post you can get the list of thumbnails separated by comma
SELECT
*,
(SELECT
GROUP_CONCAT(meta_value)
FROM
wp_postmeta
WHERE post_id = wp.ID
AND wpm.meta_key = "_thumbnail_id") AS `thumbnails`
FROM
wp_posts wp
JOIN wp_postmeta wpm
ON (wpm.post_id = wp.ID)
WHERE wpm.meta_key = "packageID"
AND wpm.meta_value = 1
ORDER BY wp.post_date
LIMIT 50
Note : GROUP_CONCAT has a limit to concat characters but you can increase this limit
To get only one thumbnail you can try this
SELECT
*,
(SELECT
(meta_value)
FROM
wp_postmeta
WHERE post_id = wp.ID
AND wpm.meta_key = "_thumbnail_id" LIMIT 1)
FROM
wp_posts wp
JOIN wp_postmeta wpm
ON (wpm.post_id = wp.ID)
WHERE wpm.meta_key = "packageID"
AND wpm.meta_value = 1
ORDER BY wp.post_date
LIMIT 50
Try this
SELECT * FROM wp_posts P1
LEFT JOIN wp_postmeta M1 ON (M1.post_id=P1.ID)
WHERE (M1.meta_key = "packageID" and M1.meta_value = 1 )
LEFT JOIN wp_postmeta M2 ON (M2.meta_key=P1.ID AND M2.meta_key = '_thumbnail_id')
LEFT JOIN wp_posts P2 ON (M2.meta_value=P2.ID)
ORDER BY P1.post_date limit 50
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