Read in loop

Hi all ,
      I have one internal table itab1 as
mblnr    zeile   vgbel   lifnr
11     1     z           08
11     2     z           77
11     3     z           76
11     4     z           75
11     5     z           08
12        1     z           76
12     2     z           75
12     3     z           77
12     4     z           76
12     5     z           77
13     1     z            77
13     2     z            76
13     3     z            77
Another   itab2   as
vbeln   zeile     vgbel
A     1     z
A     2     z
A     3     z
A     4     z
A     5     z
B     1     z
B     2     z
B     3     z
B     4     z
B     4     z
C     1     z
C     1     z
C     1     z
Mblnr should link to vbeln in asending order i.e: A for 11 etc .,
There is no direct linkage I could find in between mblnr & vbeln and even for lifnr .So recordpointers are based only on vgbel & zeile .
Loop at itab1 into ls_a1 .
Read table itab2 into ls_b1
   with key vgbel = ls_a1-vgbel
                                            Zeile = ls_a1-zeile .
V_tabix = sy-tabix .
Do something.
Modify itab1 from ls_a1 .
Delete ls_b1 index v_tabix .
Delete itab1 .
Endloop.
Itab1-mblnr corresponds to itab1-vbeln .
So for a selection from mblnr 11 to 13 , every thing works fine .But if I select for a lifnr 77
Itab1 contains
mblnr    zeile   vgbel   lifnr
11     2     z           77
12     3     z           77
12     5     z           77
13     1     z            77
13     3     z            77
and itab2 is as it is .
But with the same logic ,
For sy-index 1 of itab1   its right .
Now for the sy-index 2   of itab1 , read table can indicate itab2 as
A         3      z   instead of    B   3   z   because no direct link is there in between A B C and 11 22 33 .
Is there any way I can read the proper record from itab2 ? any other internal table validation of zeile with respect to mblnr and vbeln or any ztable ?
              Any help !!!
Regards ,
Sun

Hi,
Perhaps you could delete all those details in itab2 which has more entries at END OF mblnr of itab1.
Check this...
DATA sytabix LIKE sy-tabix.
DATA v_vbeln LIKE itab2-vbeln.
LOOP AT itab1.
READ TABLE ITAB2 WITH KEY vgbel = itab1-vgbel
zeile = itab1-zeile.
sytabix = sy-tabix.
"Store the matching entry in a var
v_vbeln = itab2-vbeln.
"Do your processing here
DELETE itab2 INDEX sytabix.
 AT END OF mblnr.
"When a particular sequence of mblnr finishes delete the prev entries
DELETE itab2 WHERE vbeln EQ v_vbeln.
ENDAT.
ENDLOOP.
Ps: Reward helpful posts.
Regards,
Wenceslaus.

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Attachments:
myVi.GIF ‏72 KB

I was working quickly, and from memory, so my apologies for errors or non-clarity in my previous post. :-(
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When the task is complete (your WHILE loop is done), then call the AI CLEAR task to clean up (ONCE).
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If you do this, you have to read the data often enough to avoid buffer overflow, which means the incoming data is filling up the buffer faster than you're emptying it.
I have attached a picture of the general idea. If you really want to use the CPU efficiently, then consider the shift-register idea in the picture - you process on batch of data WHILE the next batch is coming in. If you want a simpler solution, forget the shift-reg, and process it directly after reading it. If your buffer is twice the size of your processing size, you'll be OK.
Message Edited by CoastalMaineBird on 09-14-2005 07:45 PM
Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com
Blog for (mostly LabVIEW) programmers: Tips And Tricks
Attachments:
DAQExample.png ‏16 KB

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I have one internal table lets ITAB1[] ,
Its having 15,0000 Records.
now I want to search only 5 records from ITAB1[] compairing ITAB2[] , ITAB2 having 15,0000 records.
what is best method to search this records in minimum time.
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Hi,
loop it ITAB1.
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Endloop.
I think whatever code you are using now is appropriate only.
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I have tried the following:
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Message was edited by: Sekhar

Can put condition in read statement for a particular fild please suggest?

hi i have a requirement as belo
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where status<> Z
to add to this read statement as below can i add the above condition to the below statement?? let me know
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Hello arora.
You can restrict the READ to an internal table, using "n" conditions in WITH KEY statement.
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HI Friends,
I am using a code like as below
loop at itab assigning <fl_itab>.
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my questio is .
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Yes it will take the first record.
you can check the sy-subrc value after the execution of the READ statement.
loop at itab assigning <fl_itab>.
read table inttab assigning <fl_inttab> with key matnr = <fl_itab-matnr>.
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Have an issue with performance. I have a couple of scenarios:
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Don't spend your time to imagine what is you exact problem in your program trace your program which database sql take longer time useing the ST05 try to avoid the bulk data read in loop if possible.
You mention in point 1 it is correct.
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Just read some chunk of data and process (ie. read maximum of 50-50 record and process).
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If the question is already answered then you forgot to give points!
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loop at itab2.   ( a records, a constant)
or
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/people/siegfried.boes/blog/2007/09/12/runtimes-of-reads-and-loops-on-internal-tables
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Read statement drawback

Dear friends,
I am using read statement :
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10003 55.50
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Hello,
But IT_BKPF will have only one record for BELNR, BUKRS & GJAHR combination.
So you can loop at IT_BSID & read IT_BKPF, simple )
LOOP AT it_bsid.
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I will not suggest nested LOOP stmt like this:
LOOP AT it_bkpf.
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ENDLOOP.
ENDLOOP.
Hope this helps.
BR,
Suhas

Read Statement Issue

HI,
I am facing problem with read statement, please find below my code and provide the solution.
My Internal Tables.
TYPES: BEGIN OF TYP_BSAK,
BUKRS TYPE BSAK-BUKRS,
LIFNR TYPE BSAK-LIFNR,
AUGDT TYPE BSAK-AUGDT,
GJAHR TYPE BSAK-GJAHR,
BELNR TYPE BSAK-BELNR,
BUZEI TYPE BSAK-BUZEI,
BUDAT TYPE BSAK-BUDAT,
BLART TYPE BSAK-BLART,
DMBTR TYPE BSAK-DMBTR,
SGTXT TYPE BSAK-SGTXT,
AUGBL TYPE BSAK-AUGBL,
HKONT TYPE BSAK-HKONT,
END OF TYP_BSAK.
DATA : IT_BSAK TYPE STANDARD TABLE OF TYP_BSAK WITH HEADER LINE,
WA_BSAK TYPE TYP_BSAK.
READ STATEMENT :
LOOP AT IT_BSIS INTO WA_BSIS.   -> I am getting data in wa_BSIs
   READ TABLE IT_BSAK INTO WA_BSAK -> I am Getting record in IT_BSAK bu the same is not populated in WA_BSAK
   WITH KEY BUKRS = S_BUKRS.
   IF SY-SUBRC = 0.
      WA_OUTPUT-SAPSYS    = 'PROBE'.
      WA_OUTPUT-BUKRS     = WA_BSAK-BUKRS.
      WA_OUTPUT-BUKRS     = WA_BSAK-BUKRS.
      WA_OUTPUT-BELNR     = WA_BSAK-BELNR.
      WA_OUTPUT-SGTXT     = WA_BSAK-SGTXT.
      WA_OUTPUT-BUDAT     = WA_BSAK-BUDAT.
      WA_OUTPUT-AUGBL     = WA_BSAK-AUGBL.
      WA_OUTPUT-LIFNR     = WA_LFA1-LIFNR.
      WA_OUTPUT-NAME1     = WA_LFA1-NAME1.
      WA_OUTPUT-STRAS     = WA_LFA1-STRAS.
      WA_OUTPUT-ORT01     = WA_LFA1-ORT01.
      WA_OUTPUT-REGIO     = WA_LFA1-REGIO.
      WA_OUTPUT-PSTLZ     = WA_LFA1-PSTLZ.
      WA_OUTPUT-STCD2     = WA_LFA1-STCD2.
     ENDIF.
APPEND WA_OUTPUT TO IT_OUTPUT.
   ENDLOOP.
Thanks and Regards
VB

Hi,
I hope You have use below code solved your problem.
LOOP AT IT_BSIS INTO WA_BSIS
READ TABLE IT_BSAK INTO WA_BSAK
WITH KEY BUKRS = WA_BSIS-BUKRS.
IF SY-SUBRC = 0.
WA_OUTPUT-SAPSYS = 'PROBE'.
WA_OUTPUT-BUKRS = WA_BSAK-BUKRS.
WA_OUTPUT-BUKRS = WA_BSAK-BUKRS.
WA_OUTPUT-BELNR = WA_BSAK-BELNR.
WA_OUTPUT-SGTXT = WA_BSAK-SGTXT.
WA_OUTPUT-BUDAT = WA_BSAK-BUDAT.
WA_OUTPUT-AUGBL = WA_BSAK-AUGBL.
WA_OUTPUT-LIFNR = WA_LFA1-LIFNR.
WA_OUTPUT-NAME1 = WA_LFA1-NAME1.
WA_OUTPUT-STRAS = WA_LFA1-STRAS.
WA_OUTPUT-ORT01 = WA_LFA1-ORT01.
WA_OUTPUT-REGIO = WA_LFA1-REGIO.
WA_OUTPUT-PSTLZ = WA_LFA1-PSTLZ.
WA_OUTPUT-STCD2 = WA_LFA1-STCD2.
ENDIF.
APPEND WA_OUTPUT TO IT_OUTPUT.
ENDLOOP.
Thanks
Regards
I.Muthukumar.
Edited by: I.Muthukumar on Jun 25, 2010 12:43 PM

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vipul

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This can be an explicit cursor, where you open the cursor and manually code the loop with the FETCH statement.
It can be an implicit cursor, where you simply code something like [SELECT col INTO var FROM table] - in which case PL/SQL still creates a cursor and still uses a cursor fetch to read the result of that cursor.
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Compare two DAQmx Read modes

For a continuous DAQmx acquisition, generally a start VI is put before a loop structure to request DAQ board to begin continuously reading data into buffer, and within loop a DAQmx read VI is used to continuously retrieve data from buffer.
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For my application, read only one data in each loop is easier for teatment, but I am concerning whether more frequent loop execution may cause decrease of performance. Any suggestion?
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Message Edited by Dejun on 08-30-2007 05:16 PM

Read in loop

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