manoj,
there is some minor correction in your query.
SELECT DISTINCT ID, post_title, post_name, guid, post_date, post_content
FROM wp_posts AS p
INNER JOIN wp_term_relationships AS tr ON (
p.ID = tr.object_id
)
INNER JOIN wp_term_taxonomy AS tt ON (
tr.term_taxonomy_id = tt.term_taxonomy_id
AND taxonomy = 'category' AND tt.term_id
IN ( 16 )
)
ORDER BY id DESC
