Make a SELECT by field is empty?

Question

I need to know how to make a comparison in a SELECT for a field that has to be empty.

I'm trying to select some fields from bkpf, with the field stblg as empty. I've done it in this way:

 SELECT c~kunnr a~belnr d~spart c~bldat c~waers a~hwaer f~mwskz
      INTO CORRESPONDING FIELDS OF TABLE lt_data
        FROM ( ( ( bsis AS f
      INNER JOIN bkpf AS a ON f~belnr = a~belnr )
      INNER JOIN bsad AS c ON c~belnr = a~belnr )
      INNER JOIN vbrk AS d ON d~vbeln = c~belnr )
      WHERE a~gjahr IN gjahr
        AND a~bukrs IN bukrs
        AND c~augdt IN augdt
        AND a~stblg = ' '
        AND f~hkont = '0034930020'.

Is this correct or do I have to use another thing? Thank you.

Answer 1

In your case, you can use AND a~stblg = ' ' or the already mentioned AND a~stblg EQ SPACE - there is no difference (I would recommend to use SPACE. With ' ' you can't be sure, if you want to check a space or if you forgot to fill something in the '.)

On database level empty can have another meaning. Databases make a difference between space or ' ' and no value (NULL).

You can check NULL in SAP with:

AND a~stblg IS NULL

In your case, this statement should select nothing, because SAP normally stores space for empty character values.