urgent help wp_post2cat doesn’t exist

Hello there ,
I upgraded WP yesterday to 2.3 , my earlier version was 2.2 , I did not post anything yesterday ,I kept updating all the plugins
today I posted earlier and I faced this problem , every time I try to post anything ,when I hit the publish button,I found this error page loaded and is saying

WordPress database error: [Table ‘XXXX_wp.wp_post2cat’ doesn’t exist]
SELECT cat_ID AS ID, MAX(post_modified) AS last_mod FROM wp_posts p LEFT JOIN wp_post2cat pc ON p.ID = pc.post_id LEFT JOIN wp_categories c ON pc.category_id = c.cat_ID WHERE post_status = ‘publish’ GROUP BY cat_ID

Warning: Cannot modify header information – headers already sent by (output started at /home/www/XXXXXXXXXX/wp-includes/wp-db.php:160) in /home/www/XXXXXXXXXXXX/wp-includes/pluggable.php on line 390″
I know it is about the database , but when
the strange thing is that post will be posted fine in the front page
another thing when I upgraded WP ,the upgrade wizard informed me that It would update the database and It did

what shall I do ??