MySQL Select rows on first occurrence of each unique value

Question

Let\'s say you have the following table (the column of interest here is cid):

+-----+-------+-------+-------+---------------------+-------------         


        

Answer 1

Try this one,

SELECT *
FROM tableName a 
INNER JOIN (
    SELECT cid, MIN(`time`) AS MinTime
    FROM tableName
    GROUP BY cid
) b 
ON a.CID = B.cid AND a.time = b.MinTime