topic Re: Using internal table & Loop VS. select & EndSelect in Application Development and Automation Discussions

Using internal table & Loop VS. select & EndSelect

Former Member — Mon, 03 Dec 2012 11:24:56 GMT

Hi,

Please help me to know which selection is better:

option 1:

SELECT MAX( LETZTZUG ) MAX( LETZTABG ) MAX( LETZTVER ) MAX( LETZTBEW )

INTO table lt_dates

FROM S032

WHERE VRSIO = '000'

AND matnr = lwa_output-IDNRK

AND werks = lwa_output-werks.

loop at lt_dates into lwa_dates.

IF lwa_dates_max-LETZTZUG < lwa_dates-LETZTZUG.

lwa_dates_max-LETZTZUG = lwa_dates-LETZTZUG.

ENDIF.

IF lwa_dates_max-LETZTABG < lwa_dates-LETZTABG.

lwa_dates_max-LETZTABG = lwa_dates-LETZTABG.

ENDIF.

IF lwa_dates_max-LETZTVER < lwa_dates-LETZTVER.

lwa_dates_max-LETZTVER = lwa_dates-LETZTVER.

ENDIF.

IF lwa_dates_max-LETZTBEW < lwa_dates-LETZTBEW.

lwa_dates_max-LETZTBEW = lwa_dates-LETZTBEW.

ENDIF.

ENDLOOP.

Option 2:

SELECT MAX( LETZTZUG ) MAX( LETZTABG ) MAX( LETZTVER ) MAX( LETZTBEW )

INTO (lwa_output-LETZTZUG , lwa_output-LETZTABG , lwa_output-LETZTVER , lwa_output-LETZTBEW )

FROM S032

WHERE VRSIO = '000'

AND matnr = lwa_output-IDNRK

AND werks = lwa_output-werks.

Thanks.

Re: Using internal table & Loop VS. select & EndSelect

SharathYaralkattimath — Mon, 03 Dec 2012 12:28:17 GMT

option 1

Re: Using internal table & Loop VS. select & EndSelect

Former Member — Mon, 03 Dec 2012 13:32:41 GMT

Hi Sharath

can you explain the reason please?

Re: Using internal table & Loop VS. select & EndSelect

SharathYaralkattimath — Tue, 04 Dec 2012 05:19:42 GMT

Please read ABAP documentation , this is basics that we should get the data at one go into table, & then you can process the internal table as per your needs.

Re: Using internal table & Loop VS. select & EndSelect

former_member189631 — Tue, 04 Dec 2012 06:29:21 GMT

Hi Arieh,

The first option queries the table and get the data from db only once.

The second option queries the table and get the data from the db in multiple times.

In ABAP program we should try to reduce the db hits as much as possible to improve the performance of the application. In your case, the first option is more efficent than second option when there is more data on the table.

Ram

Re: Using internal table & Loop VS. select & EndSelect

Clemenss — Tue, 04 Dec 2012 17:15:51 GMT

The professional answer is:

It depends.

And I don't understand your code:

Option 1 with SELECT MAX... means to put the load on the database (which is almost always slower than the ABAP runtime processor). So why then loop at the table to determine max. values?

AND: Never use a LOOP INTO workarea, always use LOOP ASSIGNING <field-symbol> for the sake of performance.

SELECT ... ENDSELECT is better than people say. It saves you memory and the performance is enhanced by the system by reading blocks of data into invisible internal tables and processing them between SELECT and ENDSELECT.

If you don't write another SELECT between SELECT and ENDSELECT, then everything is fine.

Regards

Clemens