Question

i am trying to build a query to compute Which org has the highest officers attendance each month in each district?
Terms:
“District” and “loinum” mean the same thing. There are 31 districts in Massachusetts.
“Org” is a local chapter, which is in one of the Districts.
“Officers” are the positions named “WM” through “TY”.
the table is

loinum month   year  org  wm sw jw  ty
1        8     2011  Ma   0   1  1  1 
1        9     2011  CA   1   1  0  0 
1        8     2011  La   1   0  0  1 
2        7     2011  ME   1   1  1  1
2        6     2011  io   1   0  0  0  
2        9     2011  BO   1   0  0  0 
3        5     2011  Ch   1   1  1  1
3        4     2011  AL   0   0  0  1   
3        4     2011  EG   0   1  1  0

how i can compute and get the max for EACH loinum and EACH month ?

Answer 1

This is a generic solution although for specific DB’s there may be better. Create an inline view that gets the max of the values for each loinum, month, and year. Then join it back to the main table.

Note: If there’s a tie for max there will be multiple results for a given loinum, month, and year

SELECT t.* 
FROM   table1 t 
       INNER JOIN (SELECT loinum, 
                          month, 
                          year, 
                          Max(wm + sw + jw + ty) oCount 
                   FROM   table1 
                   GROUP  BY loinum, 
                             month, 
                             year) AS MAX 
         ON t.loinum = max.loinum 
            AND t.month = max.month 
            AND t.year = max.year 
            AND ( wm + sw + jw + ty ) = max.oCount

DEMO

Results

LOINUM  MONTH   YEAR    ORG WM  SW  JW  TY
1           8   2011    Ma  0   1   1   1
1           9   2011    CA  1   1   0   0
2           6   2011    io  1   0   0   0
2           7   2011    ME  1   1   1   1
2           9   2011    BO  1   0   0   0
3           4   2011    EG  0   1   1   0
3           5   2011    Ch  1   1   1   1