Question

Let’s say I have this table MyTbl

Record    Id_try   Id        Type IsOk DateOk
1         1        MYDB00125  A     0   NULL
2         1        MYDB00125  B     1   2012-07-19 20:10:05.000
3         1        MYDB00125  A     0   2012-07-25 14:10:05.000
4         2        MYDB00125  A     0   2012-07-19 22:10:05.000
5         1        MYDB00254  B     0   2012-07-19 22:10:05.000
6         1        MYDB00254  A     0   NULL
7         3        MYDB00125  A     1   2012-07-19 22:15:05.000
8         3        MYDB00125  B     1   2012-07-19 22:42:53.000
9         1        MYDB00323  A     1   2012-07-22 00:15:05.00 0
10        1        MYDB00323  C     0   NULL

And I want a group by that brings me for each Id and Type my last “Id_Try Record”.

SELECT Id, MAX(Id_Try), MyTbl.Type, IsOK, MAX(DateOk) from MyTbl
GROUP BY Id, MyTbl.Type, IsOK

Won’t do, because It’ll bring me the last Id_Try AND the last date (Date of record 3 in the example). And I don’t care if its the last date or not, I need the date of the last Id_Try.

Is this only solved by a subselect? or a having clause could do?

This is the result expected:

Record    Id_try   Id        Type IsOk DateOk
5         1        MYDB00254  B     0   2012-07-19 22:10:05.000
6         1        MYDB00254  A     0   NULL
7         3        MYDB00125  A     1   2012-07-19 22:15:05.000
8         3        MYDB00125  B     1   2012-07-19 22:42:53.000
9         1        MYDB00323  A     1   2012-07-22 00:15:05.00 0
10        1        MYDB00323  B     0   NULL

Answer 1

I think you will need to break this into two pieces:

with maxIDTry as
(
   SELECT MAX(Id_try) as maxId, ID
   FROM MyTable
   GROUP BY ID
)
SELECT * FROM MyTable as mt
INNER JOIN maxIDTry as max
ON mt.id_try = max.maxId AND mt.id = max.id