Title: permalinks and database errors
Last modified: August 18, 2016

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# permalinks and database errors

 *  Resolved [npredford](https://wordpress.org/support/users/npredford/)
 * (@npredford)
 * [18 years, 7 months ago](https://wordpress.org/support/topic/permalinks-and-database-errors/)
 * Hi,
 * I attempted to update the Permalinks structure on this blog:
 * [http://www.beybladefun.com/blog](http://www.beybladefun.com/blog)
 * I tried the CUSTOM ans set it to
 * %postname%
 * However after testing the blog links the categories showed an 404 error page 
   so
    I tried other variations after reading the codex for Troubleshooting: [http://codex.wordpress.org/Using_Permalinks](http://codex.wordpress.org/Using_Permalinks)
 * I decided to return back to the default but now I get database error on the
 * CATEGORIES
 * WordPress database error: [Table ‘beyblade_wordpress.wp_post2cat’ doesn’t exist]
   
   SELECT SQL_CALC_FOUND_ROWS wp_posts.* FROM wp_posts LEFT JOIN wp_post2cat ON (
   wp_posts.ID = wp_post2cat.post_id) WHERE 1=1 AND wp_post2cat.category_id IN (
   1, 10) AND (post_type = ‘post’ AND (post_status = ‘publish’)) GROUP BY wp_posts.
   ID ORDER BY post_date DESC LIMIT 0, 10
 * Fatal error: Call to undefined function is_tag() in /home/beyblade/public_html/
   blog/wp-includes/template-loader.php on line 38
 * AND MONTHLY ARCHIVES
    Fatal error: Call to undefined function is_tag() in /home/
   beyblade/public_html/blog/wp-includes/template-loader.php on line 38 Would appreciate
   your advice and solution to restore the blog links.

Viewing 5 replies - 1 through 5 (of 5 total)

 *  [moshu](https://wordpress.org/support/users/moshu/)
 * (@moshu)
 * [18 years, 7 months ago](https://wordpress.org/support/topic/permalinks-and-database-errors/#post-634668)
 * For the first error see the sticky post on the main page of the forum!
 *  Thread Starter [npredford](https://wordpress.org/support/users/npredford/)
 * (@npredford)
 * [18 years, 7 months ago](https://wordpress.org/support/topic/permalinks-and-database-errors/#post-634702)
 * Thanks for the reply.
 * I have read that topic but my WP 2.3 install was done over two weeks ago. I have
   the latest plugins such as Google XML Sitemaps 3.0 which works fine.
 * My errors came after testing out the Permalink structure.
 * I have tried => Date and name based option
    and left the Optional categories 
   blank.
 * I did note that each time I clicked on the Update Permalink that the screen goes
   white and show the following message:
 * Fatal error: Call to undefined method WP_Rewrite::set_tag_base() in /home/beyblade/
   public_html/blog/wp-admin/options-permalink.php on line 81
 * I haven’t changed anything else. Do you have any suggestions?
 *  [moshu](https://wordpress.org/support/users/moshu/)
 * (@moshu)
 * [18 years, 7 months ago](https://wordpress.org/support/topic/permalinks-and-database-errors/#post-634714)
 * Sounds like some corrupted (not completely uploaded) files during the upgrade…
 *  Thread Starter [npredford](https://wordpress.org/support/users/npredford/)
 * (@npredford)
 * [18 years, 7 months ago](https://wordpress.org/support/topic/permalinks-and-database-errors/#post-634723)
 * I have re-uploaded the file but there is no change. I’ve also reverted back to
   the Default Permalink but there are still errors.
 * I have a back up but am not familiar with install instructions.
 * Would you suggest I reinstall the previous back up?
 * I would appreciate it if someone experienced could assist me with this.
 *  Thread Starter [npredford](https://wordpress.org/support/users/npredford/)
 * (@npredford)
 * [18 years, 7 months ago](https://wordpress.org/support/topic/permalinks-and-database-errors/#post-634778)
 * I reuploaded the wp-includes once more and EMPTIED my CACHE. Now things are back
   to normal.
 * Thanks for your advice moshu
 * [resolved]

Viewing 5 replies - 1 through 5 (of 5 total)

The topic ‘permalinks and database errors’ is closed to new replies.

## Tags

 * [broken permalinks](https://wordpress.org/support/topic-tag/broken-permalinks/)
 * [database errors](https://wordpress.org/support/topic-tag/database-errors/)
 * [fatal error](https://wordpress.org/support/topic-tag/fatal-error/)
 * [permalinks](https://wordpress.org/support/topic-tag/permalinks/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 5 replies
 * 2 participants
 * Last reply from: [npredford](https://wordpress.org/support/users/npredford/)
 * Last activity: [18 years, 7 months ago](https://wordpress.org/support/topic/permalinks-and-database-errors/#post-634778)
 * Status: resolved

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