Empty table prefix returned instead of default 'wp_' prefix

Hi!

I am facing a redirect to wp-admin/install.php page

What i m doing is, i have wordpress installed in /blog folder under public_html, that is wordpress is the blog for my main site. i will post updates and news about various events in the blog. And i want to show 5 latest blog post on our site homepage.

To do this i have made a php include file “latest_blog_posts.inc.php”

With the following test code —

<?php
	define('WP_USE_THEMES', false);
	require('c:/wamp/www/onlyfreelancer/blog/wp-blog-header.php');
?>
<?php query_posts('showposts=5'); ?>
<?php while (have_posts()) : the_post(); ?>
<a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>"><?php the_title(); ?></a><br />
<?php endwhile;?>

Now when i load the inc page directly in browser it shows the posts ok. But when i include it in my site’s homepage it redirects me to the install.php page

Upon check i have found that the sql query to fetch siteurl value in is_blog_installed() function evaluates to this –

SELECT option_value FROM options WHERE option_name = 'siteurl'

That is instead of being “wp_options” it is simply “options”, missing the prefix. For this the siteurl value can’t be fetched and wordpress calculates that its not installed.

How to fix this? This problem only occurs when i include the inc to my site’s home page. or any other page. It works when its loaded directly in the browser.

Thanks,
Anjan