topic Re: Shall I use SELECT SINGLE?? in Application Development and Automation Discussions

Shall I use SELECT SINGLE??

Former Member — Wed, 25 Feb 2009 14:23:37 GMT

Iu2019ve retrieved MSEG-MATNR for the condition mseg-mblnr = material doc no. and mseg-mjahr = mat doc year and mseg-zeile = mat doc item.

And my retrieved data mseg data in i_mseg is like below:

Mblnru2026u2026u2026..mjahru2026..zeilen.u2026u2026.matnr

0049000242....1995......0003........YY-110

0049000242u2026.1995u2026u20260004u2026u2026.YY-120

0049000248....1995u2026u20260001u2026u2026..40-110C

0049000248u2026.1995u2026u20260002........40-200C

0049000248u2026.1995u2026u20260003........40-210

0049000248u2026.1995u2026u20260004........L-40C

Now Iu2019ll have to fetch:

MAKT-MAKTX for the condition MAKT-MATNR=MSEG-MATNR and MAKT-SPRAS = u2018ENu2019.

Shall I use select single or normal select queries for makt-maktx retrieval?

If select single, then why and if not, then why?

Can anyone please guide?

Regards.

Re: Shall I use SELECT SINGLE??

Former Member — Wed, 25 Feb 2009 14:29:30 GMT

You can retrive material texts for all the materials retreived in your table by using Select..for all entries....

Please let me knwo if this helps!

Re: Shall I use SELECT SINGLE??

Former Member — Wed, 25 Feb 2009 14:31:01 GMT

I think for all entries will work in this case but trying to be understand why not select single here?

Re: Shall I use SELECT SINGLE??

Former Member — Wed, 25 Feb 2009 14:40:54 GMT

if you use select..single you will need to use that in a loop.

So that for every material in the loop you use select single which will retrieve 1 record each for a material...

One more point for Select single ...when you use select single ...you need to provide the entire key of the table.

Re: Shall I use SELECT SINGLE??

Former Member — Wed, 25 Feb 2009 14:44:02 GMT

thanks anuradha.hope this will work.Let me check.

Re: Shall I use SELECT SINGLE??

Former Member — Wed, 25 Feb 2009 14:57:20 GMT

Hi,

It depends of how many records you expect to read. If you have a reduced amount of records I would expect for the join statement to underperform, even if the access to the data bank is faster.

But at a considerable amount of data the join might be a lot faster. Use the tc SM30 to test your code.

This is a test script (for development system):


TABLES: mseg, makt.

SELECT-OPTIONS: s_mblnr FOR mseg-mblnr,
                s_mjahr FOR mseg-mjahr,
                s_zeile FOR mseg-zeile.
PARAMETERS p_join AS CHECKBOX.

DATA: BEGIN OF l_mseg,
        mblnr LIKE mseg-mblnr,
        maktx LIKE makt-maktx,
      END OF l_mseg.

START-OF-SELECTION.
  DO 10000 TIMES.
    IF p_join IS INITIAL.
      SELECT mblnr INTO l_mseg-mblnr FROM mseg WHERE mblnr IN s_mblnr 
                            AND mjahr IN s_mjahr AND zeile IN s_zeile.
        SELECT SINGLE maktx INTO l_mseg-maktx FROM makt 
                                   WHERE matnr EQ mseg-matnr AND spras = sy-langu.
      ENDSELECT.
    ELSE.
      SELECT mblnr maktx INTO l_mseg
               FROM mseg JOIN makt ON makt~matnr = mseg~matnr
               WHERE mblnr IN s_mblnr AND mjahr IN s_mjahr AND zeile IN s_zeile
               AND spras = sy-langu.
      ENDSELECT.
    ENDIF.
  ENDDO.

regards,

Edgar