mysql group by having min

Question

Below is the table data (a small piece) basically I'm looking to query just the rows with the minimum original_date_ctr when grouped by the accoutn number.

I've tried using HAVING(MIN()), and where = Min() and other ways with no luck.

The correct result here would give me id_ctr 688, 1204 and 1209

id_ctr  account_number_cus  original_date_ctr   mrc_ctr  
------  ------------------  -----------------  ----------
   688               20062  2008-05-17             138.97
  1204              151604  2006-08-10           42000.00
  1209              151609  2006-06-29             968.68
  1367               20062  2011-10-27             207.88
  1434              151609  2009-09-10            1469.62
  1524              151604  2009-09-01           36999.99
  1585              151609  2012-05-31            1683.88

Answer 1

You can do this the following way:

select t1.id_ctr,
    t1.account_number_cus,
    t1.original_date_ctr,
    t1.mrc_ctr  
from yourtable t1
inner join
(
    select min(original_date_ctr) as mindate, account_number_cus
    from yourtable
    group by account_number_cus
) t2
    on t1.account_number_cus = t2.account_number_cus
    and t1.original_date_ctr = t2.mindate

see SQL Fiddle with Demo

Answer 2

Doing this with a join will be faster:

SELECT a.*
FROM mytable a
LEFT JOIN mytable b
  ON a.account_number_cus = b.account_number_cus
  AND b.original_date_ctr < a.original_date_ctr
WHERE b.id_ctr IS NULL