Calling a particular custom field from ALL posts

You’ll need to query the database.

Try this:

$thumbs = $wpdb->get_col("
	SELECT
		p.meta_value
	FROM $wpdb->postmeta p
	INNER JOIN $wpdb->term_relationships a
	ON p.post_id = a.object_id
	JOIN $wpdb->term_taxonomy b
	USING (term_taxonomy_id)
	JOIN $wpdb->terms c
	USING (term_id)
	WHERE p.meta_key = 'thumb'
	AND c.name = 'WORK'
");

foreach ($thumbs as $thumb)
	echo $thumb->meta_value;

That actually worked perfectly, after I removed:

AND c.name = 'WORK'

Thanks!

And as a good support forum user, here’s how this was implemented. I wanted to spit out the meta_value (image path) for all my portfolio images, so I could create a one-click slideshow with Colorbox. You will notice I added “ORDER BY meta_value ASC” to get them in order.

<?php
			// this yanks the thumb from every post
			$thumbs = $wpdb->get_col("
			SELECT p.meta_value
			FROM $wpdb->postmeta p
			INNER JOIN $wpdb->term_relationships a
			ON p.post_id = a.object_id
			JOIN $wpdb->term_taxonomy b
			USING (term_taxonomy_id)
			JOIN $wpdb->terms c
			USING (term_id)
			WHERE p.meta_key = 'thumb'
			ORDER BY meta_value ASC
			");?>

			<?php foreach ($thumbs as $thumb){
				echo
				'<a href="'.get_bloginfo('template_directory').'/'.$thumb.'" rel="slideshow"></a>
				';
			} ?>

It’s not absolutely necessary, but if I could find a way to exclude certain ones whenever I wanted, that would make this perfect.

Exclude by meta_value, that is.

c.name = 'WORK' is the category name and I just copy it exactly from your first post. I probably should have changed it to 'Work' to avoid the confusion.

Also, just want to correct a mistake in my first post in case other’s are using it. $wpdb->get_col returns an array not an object, therefore

foreach ($thumbs as $thumb)
	echo $thumb->meta_value;

should just be

foreach ($thumbs as $thumb)
	echo $thumb;

BTW, can you put this as resolved? Thanks.