I want to fetch latest 3 post from wordpress with title,description ,featured image, date of publish using mysql query or using xmlrpc api

write a query in mysql by descending your post uploaded date with limit 3

SELECT * FROM tablename ORDER BY added_date DESC limit 3

You can get the title, description and date of publish of latest 3 posts by

SELECT post_title, post_content, post_date
FROM wp_posts 
WHERE post_type='post' 
AND post_status='publish' 
ORDER BY post_date 
DESC LIMIT 3;

And featured images for the above three posts by

SELECT guid 
FROM wp_posts AS a 
INNER JOIN ( 
    SELECT meta_value 
    FROM wpsys_postmeta AS b 
    INNER JOIN ( 
        SELECT ID FROM 
        wpsys_posts 
        WHERE post_type = 'post' 
        AND post_status = 'publish' 
        ORDER BY post_date 
        DESC LIMIT 3 ) AS tbl1 
    ON b.post_id = tbl1.ID and b.meta_key='_thumbnail_id' ) as tbl2 
ON a.ID = tbl2.meta_value;

Note: 1) Check your table prefix. Here table prefix is wp_

2) Make sure featured image exists in your latest 3 posts otherwise the second query will result in failure.

<?php 
    $args = array( 'numberposts' => '3' );
    $recent_posts = wp_get_recent_posts( $args );
?>

As taken from Wordpress Codex