Knowledge Management

Question:
I programmed the following SQL statement in a report program and received short dump DBIF_RSQL_TABLE_UNKNOWN when the report is executed.
S_XXXXX are selection screen elements defined and IT_RESULT is an internal table.
The short dump message claims that table BSIK does not exist.
SELECT *
INTO CORRESPONDING FIELDS OF TABLE IT_RESULT
FROM BSIK
WHERE LIFNR IN S_LIFNR
AND CPUDT IN S_CPUDT
AND BUDAT IN S_BUDAT
AND UMSKZ IN S_UMSKZ
AND EXISTS ( SELECT *
FROM BSEG
WHERE BELNR = BSIK~BELNR
AND BUZEI = BSIK~BUZEI
AND KOART = 'K' )
AND EXISTS ( SELECT *
FROM LFA1
WHERE LIFNR = BSIK~LIFNR
AND KTOKK = S_KTOKK ).
Any thought?
Answer:
BSEG is a cluster table (see SE11).
The database doesn't know about a table BSEG (just RFBLG).
That's why< you can't use BSEG in a subquery.
IMO there IS an error in the SAP standard (SAP kernel).
The SYNTAX CHECK should complain about BSEG beeing used in a subquery.
This would be better then a run time error.