FOR ALL ENTRIES through empty itab selects all records from DB

Question

I have a query in which I am using FOR ALL ENTRIES. The internal table lt_customer has no records.

SELECT *
    FROM bsid
    INTO CORRESPONDING FIELDS OF TABLE lt_customer2
    FOR ALL ENTRIES IN lt_customer
    WHERE bukrs EQ p_bukrs
      AND belnr EQ lt_customer-belnr
      AND gjahr EQ lt_customer-gjahr.

Now, since lt_customer has no record, I am expecting a dump here. But it turns out that it was selecting all the records from bsid into lt_customer2. I don't understand why or how. Please enlighten me. Thanks!

user_8829775 · Answer

This is the standard behaviour, as documented in the ABAP Help:

"If the internal table itab is empty, the entire WHERE condition is ignored."

https://help.sap.com/doc/abapdocu_752_index_htm/7.52/en-US/abenwhere_logexp_itab.htm

Check if the table is not empty before the SELECT:

IF lt_customer IS NOT INITIAL.
  SELECT ...
  ...
  FOR ALL ENTRIES IN lt_customer
  ...
ENDIF.

user_2847159 · Answer

FOR ALL ENTRIES working look like IN operator. If itab empty then this condition ignored. You need to make manual check or add dummy record to lt_customer.

FOR ALL ENTRIES through empty itab selects all records from DB

2 Answers