Reading data from BSEG

Question

Hi,
I never read data from Cluster table like BSEG, is there any precautions to be taken while reading data from it? as it contains voluminous data
please suggest.
regards,
Pra

Answer 1

<b>Cluster Tables (BSEG,BSEC)</b>
Should be accessed via primary key - very fast retrieval otherwise very slow
No secondary indexes
Select * is Ok because all columns retrieved anyway. Performing an operation on multiple rows is more efficient than single row operations. Therefore you still want to select into an internal table. If many rows are being selected into the internal table, you might still like to retrieve specific columns to cut down on the memory required.
Statistical SQL functions (SUM, AVG, MIN, MAX, etc) not supported
Can not be buffered
SELECT bukrs belnr gjahr blart budat monat
         tcode bvorg waers kursf hwaer
  FROM   bkpf
  INTO   TABLE it_bkpf
  WHERE  bukrs IN s_bukrs
  AND    gjahr IN s_gjahr
  AND    monat IN s_monat
  AND    tcode IN ('CO88', 'KO88', 'KK87')
  AND    awtyp EQ c_ref_pro.            "'AUAK'
Pick up the corresponding line items from BSEG
  SELECT bukrs belnr gjahr dmbtr wrbtr ktosl
         zuonr hkont matnr werks menge
  FROM   bseg
  INTO   TABLE it_bseg
  FOR ALL ENTRIES IN it_bkpf
  WHERE  bukrs = it_bkpf-bukrs
  AND    belnr = it_bkpf-belnr
  AND    gjahr = it_bkpf-gjahr
  AND    werks IN s_werks
  AND    ktosl = c_tr_key.              "'PRD'
<b>BSEG Access</b>
BSAD     Accounting: Secondary index for customers (cleared items)
BSAK     Accounting: Secondary index for vendors (cleared items)
BSAS     Accounting: Secondary index for G/L accounts (cleared items)
BSID     Accounting: Secondary index for customers
BSIK     Accounting: Secondary index for vendors
BSIM     Secondary Index, Documents for Material
BSIS     Accounting: Secondary index for G/L accounts