topic SELECT inside a loop ? in Application Development and Automation Discussions

SELECT inside a loop ?

Former Member — Fri, 24 Mar 2006 09:07:19 GMT

Hello friends,

Just woundring if someone advise me something better

Actually I have a loop and inside a loop I am seleting something ( one field ). So I am using following:

Loop at lt_lfa1 into ts_lfa1.

SELECT lifnr FROM lfb1

INTO lv_lifnr

WHERE lifnr EQ ts_lfa1-lifnr

AND ....

Endloop.

Okey, as I am not selecting result in a table instead a field, i get error, that I have to provide endselect statement ( which I dont want ( due to performance reason). so the only solution I know is to use statement :

INTO CORRESPONDING FIELDS OF TABLE bla bla.. ( to avoid select endselect stuff). but as I am selecting only 1 field its also not convinient that I create a new internal table, ... so do any one here knows, how to not use select-endselect while selecting only one field ?

Many thanks

Re: SELECT inside a loop ?

Former Member — Fri, 24 Mar 2006 09:10:00 GMT

use SELECT SINGLE

SELECT SINGLE lifnr FROM lfb1
INTO lv_lifnr
WHERE lifnr EQ ts_lfa1-lifnr
AND ....

Message was edited by: Sekhar

Re: SELECT inside a loop ?

Former Member — Fri, 24 Mar 2006 09:10:34 GMT

Hi shah,

U can use

Loop at lt_lfa1 into ts_lfa1.

Select single lifnr FROM lfb1

INTO lv_lifnr

WHERE lifnr EQ ts_lfa1-lifnr

AND ....

Endloop.

thanks,

priya

Re: SELECT inside a loop ?

Former Member — Fri, 24 Mar 2006 09:11:16 GMT

Hello ,

The following code should work correctly.

DATA LT_LIFNR TYPE LIFNR OCCURS 0 WITH HEADER LINE.

SELECT LIFNR
  FROM LFB1
 INTO TABLE LT_LIFNR
  FOR ALL ENTRIES IN LT_LFA1 WHERE LIFNR = LT_LFA1-LIFNR.

LOOP AT LT_LIFNR.
  WRITE : / LT_LIFNR.
ENDLOOP.

Please do let me nkow if it worked. You just need to assign the points to this answer....:-)

Re: SELECT inside a loop ?

Former Member — Fri, 24 Mar 2006 09:12:51 GMT

hi shah,

Use Select Single Statement or Select * from dbtable in to table itab2 for all entries of itab..

Regards,

Santosh

Re: SELECT inside a loop ?

Former Member — Fri, 24 Mar 2006 09:15:04 GMT

thx for your replies:

Oh that was much simple, actually I am new to ABAP world , well point awared on the basis of first come, first serve!

Many thanks again

Re: SELECT inside a loop ?

Former Member — Fri, 24 Mar 2006 09:19:59 GMT

Hi Shah,

Actually I have a loop and inside a loop I am seleting something ( one field ). So I am using following:

I would suggest if you could avoid using a Select inside a loop due to performance reason. I would suggest you to make use of read statement using Binary search inside a loop.

Again scenario dependendent.

Suggestion steps:

1) Select the record into an internal table before loop , say itab using Array fetch.

2) Sort ur itab

3) Use Loop at lt_lfa1 into ts_lfa1.

4) In that loop used read statement along with binary search .

Using the above steps you can get read of inface Select and Endselect also.

Other wise

you can use select single inside the loop to avoid endselect , if ur reqmt. is like that only

Let me know if that helps or still if u have any doubts.

Cheers

Sunny

Rewrd points, if found helpful

Re: SELECT inside a loop ?

Former Member — Fri, 24 Mar 2006 09:34:45 GMT

Hello sunny,

thx for ur input, humm..intresting senario, which you have provide, will later give it a try, and will let you know, at the moment, have to move on to my current problem

regards/

Re: SELECT inside a loop ?

Former Member — Mon, 27 Mar 2006 06:40:22 GMT

Hi,

Using a select statement inside a loop reduces the performance and increases the run time and the frequency of Database access .

Try this code .

select lifnr into table lt_lfb1

from lfb1

where key element is not null.

Loop at lt_lfa1 into ts_lfa1.

read table lt_lfb1 into ts_lfb1 with key lifnr eq ts_lfa1-lifnr

if sy-subrc ne 0.

clear ts_lfb1 .

endif.

endloop.

Re: SELECT inside a loop ?

Former Member — Mon, 27 Mar 2006 14:02:31 GMT

Hi one could also join the two tables and loop once......