MySQL errors

I get this error in header, anyone knows what it means ?

WordPress database error: [Lost connection to MySQL server during query]
SELECT DISTINCT * FROM wp_posts WHERE 1=1 AND post_date_gmt <= ‘2006-04-29 11:32:59’ AND (post_status = “publish”) AND post_status != “attachment” GROUP BY wp_posts.ID ORDER BY post_date DESC LIMIT 0, 20

WordPress database error: [Can’t connect to local MySQL server through socket ‘/var/lib/mysql/mysql.sock’ (111)]
SELECT DISTINCT YEAR(post_date) AS year, MONTH(post_date) AS month, count(ID) as posts FROM wp_posts WHERE post_date < ‘2006-04-29 06:32:20’ AND post_date != ‘0000-00-00 00:00:00’ AND post_status = ‘publish’ GROUP BY YEAR(post_date), MONTH(post_date) ORDER BY post_date DESC