站内信对话列表sql语句

SELECT * from eg_t_message where message_id IN (

SELECT message_id FROM(

SELECT message_id,create_time,sendcustomer_id AS S,receivecustomer_id AS R FROM eg_t_message WHERE sendcustomer_id=1  
UNION
SELECT message_id,create_time,receivecustomer_id AS S,sendcustomer_id AS R FROM eg_t_message WHERE receivecustomer_id=1
ORDER BY create_time DESC

) s GROUP BY R ORDER BY create_time DESC
)