StackOverflow2013

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plurals

PO
primarykey
Id
3169851
data
AcceptedAnswerId
0
AnswerCount
0
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2010-07-03T00:46:34.920
FavoriteCount
0
LastActivityDate
2012-01-15T17:25:23.203
LastEditDate
2012-01-15T17:25:23.203
LastEditorUserId
347764
OwnerUserId
347764
ParentId
3152160
PostTypeId
2
Score
0
ViewCount
0
LastEditorDisplayName
text
Body
It's not one query, but it's a heck of a lot faster than the WordPress-hackery I posted earlier, and not very much slower than the original. I suppose it's the price to pay for correctness and while being SQL-ignorant. :P <pre><code>$potential_parents = $wpdb->get_results( "SELECT DISTINCT {$wpdb->posts}.ID, {$wpdb->posts}.post_title FROM {$wpdb->posts} LEFT JOIN $wpdb->postmeta wpostmeta ON ({$wpdb->posts}.ID = wpostmeta.post_id) LEFT JOIN $wpdb->term_relationships ON ({$wpdb->posts}.ID = $wpdb->term_relationships.object_id) LEFT JOIN $wpdb->term_taxonomy ON ($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id) WHERE $wpdb->term_taxonomy.taxonomy = 'category' AND $wpdb->term_taxonomy.term_id IN({$wpdb->escape($category_filter)}) AND {$wpdb->posts}.post_type = 'post' AND {$wpdb->posts}.post_status LIKE 'publish' AND {$wpdb->posts}.post_password = '' ORDER BY {$order_by};"); $imglists = array(); $parent_titles = array(); $count = $limit; foreach($potential_parents as $parent){ $images = $wpdb->get_results( "SELECT {$wpdb->posts}.ID FROM {$wpdb->posts} WHERE {$wpdb->posts}.post_parent = {$parent->ID} AND {$wpdb->posts}.post_type = 'attachment' AND {$wpdb->posts}.post_mime_type IN ('image/jpeg', 'image/gif', 'image/png') ORDER BY {$order_by} LIMIT 1;"); if($images){ $imglists[$parent->ID] = $images; $parent_titles[$parent->ID] = $parent->post_title; if(--$count < 1){break;} } } foreach($imglists as $parent_id => $imagelist){ $imgurl = wp_get_attachment_image_src($imagelist[0]->ID, $size); if($imgurl === false){continue;} //the image doesn't exist? $img_width = $imgurl[1]; $img_height = $imgurl[2]; $imgurl = $imgurl[0]; $selection[] = array('post_url'=>get_permalink( $parent_id ), 'post_title' => wp_specialchars($parent_titles[$parent_id]),'post_id'=>$parent_id, 'img_src'=>$imgurl, 'width'=>$img_width, 'height'=>$img_height); } return $selection; </code></pre> So basically, first grab one largish result set with all published posts in the categories. Then a bunch of smaller queries, fetching a single attachment ID every loop until the <code>$limit</code> has been filled. If you've got lots of posts in these categories without attachments, you'll waste some time here. But in our case it seems to be manageable. Still looking for that efficient single-query solution though. :)
Tags
Title
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. POSingle query for selecting a random images from X unique parents?
 singulars
 PostTypePostTypeId
 PTQuestion
PostTypePostTypeId
1. PTAnswer
UserLastEditorUserId
1. USulfben
UserOwnerUserId
1. USulfben
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. POSingle query for selecting a random images from X unique parents?
 singulars
 PostTypePostTypeId
 PTQuestion
PostsParentIdCreationDate
1. This table or related slice is empty.
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTAcceptedByOriginator
CommentsPostId
1. This table or related slice is empty.

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