Database error after 1.5 -> 2.0 upgrade: SELECT COUNT(DISTINCT ID) FROM

CamWheeler’s right (thanks!): I was unknowingly running a “hybrid” version of 1.5 and 2.x. What happened was that some of the 2.0.3 files had dates older than those on my FTP directory.

If it helps anyone else I had the exact same problem and after reading CamWheeler’s reply I tried deleting and reuploading my files one at a time. When I uploaded “wp-blog-header.php” in the root folder the error went away. I guess that means it was something inside that file that was popping the error.

I completely agree with Stevenw721; i recently noticed this error message at the bottom of my home page at the end of the very last post:
“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 ” at line 1]
SELECT COUNT(DISTINCT ID) FROM “

All i had to do was replace the current “wp-blog-header.php” on my server with a fresh copy of the same file.
I downloaded 2.05 and only grabbed this file and over wrote the file. In my case the file on my server was newer than the file I was uploading.
Everything works very well again and I am able to see the link for previous postings.

Well none of them didn’t work for me. So I edited template like this…
I found the code piece(it varies from template to template):

if ( !$max_page ) {
if ( isset($max_num_pages) ) $max_page = $max_num_pages;
else {
preg_match('#FROM\s(.*)\sGROUP BY#siU', $request, $matches);
$fromwhere = $matches[1];
$numposts = $wpdb->get_var("SELECT COUNT(DISTINCT ID) FROM $fromwhere");
$max_page = $max_num_pages = ceil($numposts / $posts_per_page);
}
}..........

and replaced it by

<div class="navigation">
<div class="alignleft"><?php next_posts_link('« Previous Entries') ?></div>
<div class="alignright"><?php previous_posts_link('Next Entries »') ?></div>
</div>

found in default wordpress template. Now pagination is working normally and there is no any more errors.