How to run a WP_Query on both wp_posts and wp_postmeta simultaneously?

The code here is relevant..
http://codex.wordpress.org/Displaying_Posts_Using_a_Custom_Select_Query

Namingly this part…

<?php
	$querystr = "
	SELECT wposts.*
	FROM $wpdb->posts wposts, $wpdb->postmeta wpostmeta
	WHERE wposts.ID = wpostmeta.post_id
	AND wpostmeta.meta_key = 'tag'
	AND wpostmeta.meta_value = 'email'
	AND wposts.post_status = 'publish'
	AND wposts.post_type = 'post'
	AND wposts.post_date < NOW()
	ORDER BY wposts.post_date DESC
	";
	$pageposts = $wpdb->get_results($querystr, OBJECT);
?>

You can use that as a reference to create a joined query, just modify as required..

Thanks a lot MichaelH, it’s very useful.

$params=array(
'showposts'=>3,
'post_type' => 'post',
'post_status' => 'publish,pending',
'meta_key'=>'dataX',
'meta_value'=>'Y'
);
$query = new WP_Query;
$results = $query->query($params);

This just spits out 3 instances of Y…

Hi!

Yes, I’m with the same trouble as seborgarsen, I need to use two meta keys on a query: One to filtering posts and another to sort them.

This is my query so far:

SELECT DISTINCT wposts.*
  FROM wp_posts wposts
  LEFT JOIN wp_postmeta wpostmeta ON wposts.ID = wpostmeta.post_id
  LEFT JOIN wp_term_relationships ON (wposts.ID = wp_term_relationships.object_id)
  LEFT JOIN wp_term_taxonomy ON (wp_term_relationships.term_taxonomy_id = wp_term_taxonomy.term_taxonomy_id)
WHERE wp_term_taxonomy.taxonomy = 'category'
AND wp_term_taxonomy.term_id IN(4,18,19,20,21)
AND wpostmeta.meta_key = 'engine'
AND wpostmeta.meta_value+0 >= 7.5
AND wpostmeta.meta_key = 'weight'
ORDER BY wpostmeta.meta_value+0 desc LIMIT 25

Could I be asking too much?

Thanks in advance!