Database Error with previous_post_link and next_post_link functions

[neonwired]

Passing a value of 1 or true for the in_same_cat argument results in a database error.

WordPress database error: [You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') WHERE p.post_date < '2012-10-14 17:16:13' AND p.post_type = 'project' AND p.po' at line 1]
SELECT p.* FROM wp_posts AS p INNER JOIN wp_term_relationships AS tr ON p.ID = tr.object_id INNER JOIN wp_term_taxonomy tt ON tr.term_taxonomy_id = tt.term_taxonomy_id AND tt.taxonomy = 'category' AND tt.term_id IN () WHERE p.post_date < '2012-10-14 17:16:13' AND p.post_type = 'project' AND p.post_status = 'publish' AND tt.taxonomy = 'category' ORDER BY p.post_date DESC LIMIT 1

[SergeyBiryukov]

Could not reproduce neither in 3.4.2 with Twenty Eleven nor in 3.5-beta2 with Twenty Twelve.

My steps:

1. Open single.php, add true to the previous_post_link() and next_post_link() calls:

   <?php previous_post_link( '%link', __( '<span class="meta-nav">&larr;</span> Previous', 'twentyeleven' ), true ); ?>
   <?php next_post_link( '%link', __( 'Next <span class="meta-nav">&rarr;</span>', 'twentyeleven' ), true ); ?>
   

2. The post is displayed correctly, without a database error.

Could you provide some steps to reproduce the issue on a clean install?

[duck_]

The SQL is invalid due to missing term IDs in AND tt.term_id IN (). Not sure how this happened.

[neonwired]

This may only effect custom post type will confirm if this is the case.

[neonwired]

Tested it by adding a custom post type to the twenty eleven theme, no other edits, all plugins disabled still results in the same database error.

[SergeyBiryukov]

Confirmed with a custom post type. $cat_array is empty in that case.

[nacin]

That appears good.

[nacin]

Duplicate of #15959.