Problem: Select Database to get X highest entries in reagrd to one field

Question

Hi Forum,
I have a problem regarding a complicated (at least for me) Select statement. It uses a customer Z-table to read certain data.
But my goal is to read only a certain number of top entries per store.
The number can change from one run to the other.
To make it clearer here is the simplified defintion of the database table
MANDT
LOCNR
DELTAVERS
LOCNR is a store and DELTAVERS is a version (simple counter 001,002,..)of that entry. Both fields are key fields.
Of course there additional fields with values that I interested in. But they are left out here to let focus on the problem.
My goal is to read a certain #number of top DELTAVERS (versions) for each LOCNR(Store). I do not know the stores or the # of DELTAVERS.
The select should provide a internal table showing the X highest DELTAVERS with the related store
e.g. A Select that should show the 3 highest DELTAVERS per Store LOCNR, if available
LOCNR: DELTAVERS:
N001 0013
N001 0023
N001 0024
B235 0021
B235 0056
Note: In this example B235 has only two entries
Code:
     l_having_by_cond = "count( DELTAVERS ) le  3".
       SELECT
                  locnr
                  deltavers
                  FROM z_locnr_version
                  APPENDING CORRESPONDING FIELDS OF TABLE
                  lt_locnr_version                 
                  GROUP BY locnr deltavers
                  HAVING (l_having_by_cond).
                  ORDER BY locnr deltavers DESCENDING.
lt_locnr_version should hold the desired result.
It seems to use the count for all entries and not just for each LOCNR.
Hoiw can I achive that the internal table holds the three highest DELTAVERS for each LOCNR (Store).
Or what would be the best solution here !? Remember we talking here about 1000+ Stores.
Please help !!
Thanks in advance,
Chris

Answer 1

Hi Forum
me again, I believe that I somewhat missunderstood the concept of GROUP BY and HAVING clause.
Both might prove completely useless in this case.
Would actually aa simple UP TO N ROWS do the tricking providing that the Select is done per store !?
How can I ensure that it gets always the TOP N entries!??
Thanks,
Chris
> Hi Forum,
>
> I have a problem regarding a complicated (at least
> for me) Select statement. It uses a customer Z-table
> to read certain data.
>
> But my goal is to read only a certain number of top
> entries per store.
> The number can change from one run to the other.
>
> To make it clearer here is the simplified defintion
> of the database table
> 
> MANDT
> LOCNR
> DELTAVERS
> 
>
>
> LOCNR is a store and DELTAVERS is a version (simple
> counter 001,002,..)of that entry. Both fields are key
> fields.
> Of course there additional fields with values that I
> interested in. But they are left out here to let
> focus on the problem.
>
> My goal is to read a certain #number of top DELTAVERS
> (versions) for each LOCNR(Store). I do not know the
> stores or the # of DELTAVERS.
>
> The select should provide a internal table showing
> the X highest DELTAVERS with the related store
>
> e.g. A Select that should show the 3 highest
> DELTAVERS per Store LOCNR, if available
>
>
> LOCNR: DELTAVERS:
> N001 0013
> N001 0023
> N001 0024
> B235 0021
> B235 0056
> ....
>
>
>
> Note: In this example B235 has only two entries
>
>
>
> Code:
>
>            
>      l_having_by_cond = "count( DELTAVERS ) le  3".
>
>        SELECT
>                   locnr
>                   deltavers
>
>                   FROM z_locnr_version
>                  
> APPENDING CORRESPONDING FIELDS OF
> SPONDING FIELDS OF TABLE
>                   lt_locnr_version                 
>                
>                   GROUP BY locnr deltavers
>                   HAVING (l_having_by_cond).
> ORDER BY locnr deltavers
> BY locnr deltavers DESCENDING.
> 
>
>
> lt_locnr_version should hold the desired result.
>
> It seems to use the count for all entries and not
> just for each LOCNR.
> Hoiw can I achive that the internal table holds the
> three highest DELTAVERS for each LOCNR (Store).
>
> Or what would be the best solution here !? Remember
> we talking here about 1000+ Stores.
>
> Please help !!
>
> Thanks in advance,
>
> Chris