While select join map

Hi all,

is it generally possible to write a query in a class that choses records from a table and a map?

The table would be LedgerJournalTrans , the map: CustVendTransOpen.

The tabel  LedgerJournalTrans has a customized field that contains recids from tables custTransOpen or VendTransOpen.

I need something like this:

while select forupdate LedgerJournalTrans

join  CustVendTransOpen where CustVendTransOpen.recId == LedgerJournalTrans.cutVendTransOpenRecID