Intenal table logic

Hello All,

I have 3 internal tables it_bkpf, it_bseg, it_zficash.

IN first it_bkpf the fields are BUKRS,

BELNR,GJAHR, BLART,BUDAT,MONAT.

In second IT it_BSEG the fields are BUKRS BELNR GJAHR DMBE2 HKONT PRCTR.

But Once we get the data from these tables , we need to compare the data which is maintianed in custom table it_zficash. In it_zficash the fields are 'FROM_HKONT' 'TO_HKNOT''FROM_BUKRS', 'TO_BUKRS','PRCTR','IN_BLART','EX_BLART'.

once comparison is over I need poplate only DMBE2 field from IT_BSEG .

In selection screen I am giving the period BKPF-MOnAT, Fiscal year BKPF-GJAHR.

We can't use join in this because BSEG table is Culstable.

Please help me in this.

regards,

Ajay