How to join the tables KNBK and TIBAN? - abap

Question

I am trying to read the table TIBAN only in the cases when the field BANKN of the KNBK table contains the string "IBAN". The problem that I am having is reading the table TIBAN. For the KNBK table I used the key kunnr to search the table, but the table TIBAN does not contain this field. The code is as follows:
LOOP AT lt_data_bsec ASSIGNING <ls_data_bsec>.
READ TABLE lt_data_knbk ASSIGNING FIELD-SYMBOL(<ls_data_knbk>)
WITH KEY kunnr = <ls_data_bsec>-kunnr BINARY SEARCH .
IF <ls_data_knbk>-bankn_kn CS '<IBAN>'.
>>>>> READ TABLE lt_data_tiban ASSIGNING FIELD-SYMBOL(<ls_data_tiban>).
IF <ls_data_bsec> IS ASSIGNED
AND <ls_data_tiban> IS ASSIGNED
AND ( <ls_data_bsec>-banks_bs NE <ls_data_tiban>-banks_kn
OR <ls_data_bsec>-bankl_bs NE <ls_data_tiban>-bankl_kn
OR <ls_data_bsec>-bankn_bs NE <ls_data_tiban>-bankn_kn ).
ENDIF.
The declaration of the lt_data_knbk table is:
SELECT kunnr,
banks AS banks_kn,
bankl AS bankl_kn,
bankn AS bankn_kn
FROM knbk
INTO TABLE #DATA(lt_data_knbk)
FOR ALL ENTRIES IN #lt_data_bsec
WHERE kunnr = #lt_data_bsec-kunnr
ORDER BY PRIMARY KEY.
And the declaration of the lt_data_tiban is:
SELECT banks AS banks_tb,
bankl AS bankl_tb,
bankn AS bankn_tb
FROM tiban
INTO TABLE #DATA(lt_data_tiban).
Also the declaration of the lt_data_bsec is of the type gty_out:
BEGIN OF gty_out,
bukrs TYPE bukrs,
belnr TYPE belnr_d,
buzei TYPE buzei,
budat TYPE budat,
kunnr TYPE kunnr,
banks_kn TYPE banks,
bankl_kn TYPE bankk,
bankn_kn TYPE bankn,
banks_bs TYPE banks,
bankl_bs TYPE bankk,
bankn_bs TYPE bankn,
banks_tb TYPE banks,
bankl_tb TYPE bankk,
bankn_tb TYPE bankn,
END OF gty_out,
I am having an error in the line that I have marked in the code as it needs a key field to do the reading of the table.
May anyone know what type of field do I need to do a search of the TIBAN table, just like I did for the KNBK table?

Answer 1

I would recommend you to acquire your bank data by doing a LEFT OUTER JOIN with TIBAN.
SELECT knbk~kunnr AS kunnr,
knbk~banks AS banks_kn,
knbk~bankl AS bankl_kn,
knbk~bankn AS bankn_kn,
knbk~bkont AS bkont_kn,
tiban~iban AS iban
FROM knbk
LEFT OUTER JOIN tiban ON
tiban~banks = knbk~banks AND
tiban~bankl = knbk~bankl AND
tiban~bankn = knbk~bankn AND
tiban~bkont = knbk~bkont
INTO TABLE #DATA(lt_data_knbk)
FOR ALL ENTRIES IN #lt_data_bsec
WHERE knbk~kunnr = #lt_data_bsec-kunnr
ORDER BY knbk~banks knbk~bankl knbk~bankn knbk~bkont.
The result will be a table with all entries from KNBK, plus a field IBAN which will be filled from TIBAN if a corresponding row exists and be initial when no corresponding row exists.
Now you can just determine whether or not you have an IBAN like this:
LOOP AT lt_data_knbk ASSIGNING FIELD-SYMBOL(<ls_data_knbk>).
IF <ls_data_knbk>-iban IS INITIAL.
" classic bank number + account number account
ELSE.
" IBAN account
ENDIF.
ENDLOOP.

Answer 2

Your task is a perfect case where ABAP CDS associations aka Lazy Join come into play.
If you are on the recent version of ABAP and is able to create CDS, nothing prevents you from creating this
#AbapCatalog.sqlViewName: ‘ZCUST_TIBAN_SQL’
#AbapCatalog.compiler.compareFilter: true
#AccessControl.authorizationCheck: #CHECK
#EndUserText.label: ‘TIBAN’
define view ZCUST_TIBAN as select from knbk as cus
association [0..1] to tiban as _an
on cus.kunnr = _an.kunnr
and cus.banks = _an.banks
and cus.bankl = _an.bankl
and cus.bankn = _an.bankn
and cus.bkont = _an.bkont
{
cus.kunnr,
cus.banks AS banks_kn,
cus.bankl AS bankl_kn,
cus.bankn AS bankn_kn,
cus.bkont AS bkont_kn,
_iban~
} WHERE cus.bankn like '%IBAN%'
Then you can use this association in all your further requirements:
SELECT banks_kn, bankl_kn, bankn_kn, bkont_kn
\_iban-iban AS IBAN,
\_iban-valid_from AS IBAN_validity
FROM zcust_tiban
WHERE kunnr IN #lr_customers
INTO TABLE #DATA(lt_data_knbk).
...
READ TABLE lt_data_knbk ASSIGNING FIELD-SYMBOL(<ls_data_knbk>)
WITH KEY kunnr = <ls_data_bsec>-kunnr BINARY SEARCH.
...
Key points to pay attention to:
an association with 0..1 cardinality like above does not do actual JOIN until the fields from the associated table TIBAN are requested like in the above SELECT. This can be more performant and more universal than LEFT OUTER JOIN approach suggested by Philipp.
it is reusable and can be used in further selects/associations as a source