Problem with Select Statements

Question

Hi All,
I have a performance problem for my report because of the following statements.
How can i modify the select statements for improving the performance of the report.
DATA : shkzg1h  LIKE bsad-shkzg,
         shkzg1s  LIKE bsad-shkzg,
         shkzg2h  LIKE bsad-shkzg,
         shkzg2s  LIKE bsad-shkzg,
         shkzg1hu LIKE bsad-shkzg,
         shkzg1su LIKE bsad-shkzg,
         shkzg2hu LIKE bsad-shkzg,
         shkzg2su LIKE bsad-shkzg,
         kopbal1s  LIKE bsad-dmbtr,
         kopbal2s  LIKE bsad-dmbtr,
         kopbal1h  LIKE bsad-dmbtr,
         kopbal2h  LIKE bsad-dmbtr,
         kopbal1su  LIKE bsad-dmbtr,
         kopbal2su  LIKE bsad-dmbtr,
         kopbal1hu  LIKE bsad-dmbtr,
         kopbal2hu  LIKE bsad-dmbtr.
*These statements are in LOOP.
    SELECT shkzg SUM( dmbtr )
      INTO (shkzg1s , kopbal1s)
      FROM bsid
     WHERE bukrs = ibukrs
       AND kunnr = ktab-kunnr
       AND budat < idate-low
       AND shkzg = 'S'
       AND umskz EQ ''
     GROUP BY shkzg.
    ENDSELECT.
    SELECT shkzg SUM( dmbtr )
      INTO (shkzg1su , kopbal1su)
      FROM bsid
     WHERE bukrs = ibukrs
       AND kunnr = ktab-kunnr
       AND budat < idate-low
       AND shkzg = 'S'
       AND umskz IN zspgl
     GROUP BY shkzg.
    ENDSELECT.
    SELECT shkzg SUM( dmbtr )
      INTO (shkzg1h , kopbal1h)
      FROM bsid
     WHERE bukrs = ibukrs
       AND kunnr = ktab-kunnr
       AND budat < idate-low
       AND shkzg = 'H'
       AND umskz EQ ''
     GROUP BY shkzg.
    ENDSELECT.
    SELECT shkzg SUM( dmbtr )
      INTO (shkzg1hu , kopbal1hu)
      FROM bsid
     WHERE bukrs = ibukrs
       AND kunnr = ktab-kunnr
       AND budat < idate-low
       AND shkzg = 'H'
       AND umskz IN zspgl
     GROUP BY shkzg.
    ENDSELECT.
    SELECT shkzg SUM( dmbtr )
      INTO (shkzg2s , kopbal2s)
      FROM bsad
     WHERE bukrs = ibukrs
       AND kunnr = ktab-kunnr
       AND budat < idate-low
       AND shkzg = 'S'
       AND umskz EQ ''
     GROUP BY shkzg.
    ENDSELECT.
    SELECT shkzg SUM( dmbtr )
      INTO (shkzg2su , kopbal2su)
      FROM bsad
     WHERE bukrs = ibukrs
       AND kunnr = ktab-kunnr
       AND budat < idate-low
       AND shkzg = 'S'
       AND umskz IN zspgl
     GROUP BY shkzg.
    ENDSELECT.
    SELECT shkzg SUM( dmbtr )
      INTO (shkzg2h , kopbal2h)
      FROM bsad
     WHERE bukrs = ibukrs
       AND kunnr = ktab-kunnr
       AND budat < idate-low
       AND shkzg = 'H'
       AND umskz EQ ''
     GROUP BY shkzg.
    ENDSELECT.
    SELECT shkzg SUM( dmbtr )
      INTO (shkzg2hu , kopbal2hu)
      FROM bsad
     WHERE bukrs = ibukrs
       AND kunnr = ktab-kunnr
       AND budat < idate-low
       AND shkzg = 'H'
       AND umskz IN zspgl
     GROUP BY shkzg.
    ENDSELECT.

Answer 1

>
Siegfried Boes  wrote:
> Please stop writing answers if you understrand nothing about database SELECTS!
> All above recommendations are pure nonsense!
>
> As always with such questions, you must do an analysis before you ask! The coding itself is perfectly o.k., a SELECT with an aggregate and a GROUP BY can not be changed into a SELECT SINGLE or whatever.
>
> But your SELECTS mustr be supported by indexes!
>
> Please run SQL Trace, and tell us the results:
>
> I see 8 statements, what is the duration and the number of records coming back for each statement?
> Maybe only one statement is slow.
>
> See
> SQL trace:
> /people/siegfried.boes/blog/2007/09/05/the-sql-trace-st05-150-quick-and-easy
>
>
> Siegfried
Nice point there Siegfried. Instead of giving constructive suggestion, people here give a very bad suggestion on using SELECT SINGLE combined with SUM and GROUP BY.
I hope the person already look at your reply before he try using select single and wondering why he has error.
Anyway, the most important thing is how many loop expected for those select statements?
If you have like thousands of loop, you can expect a poor performance.
So, you should also look at how many times the select statement is called and not only performance for each select statement when you're doing SQL trace.
Regards,
Abraham