CISAM transactions question

I want to know if there is any way to get around the requirement that a CISAM transaction must include the open and close of the database. (Bottom of page 5-7 CISAM manual) "It is very important that you open and close the file within the transaction." The problem is that I have some updates that are essentially serial in nature and affect large numbers of records in two files. Ideally I want to read serially through one file and update it and another. For each record in the first file there are several updates that form a 'transaction'. If I have to open and close the file for each transaction this is going to be *very* slow. Quite apart from the question "how do I read serially on an index when I have to close the file after every read?" The only way I see of doing this at all is to read serially through the file caching the keys of the records I want. Then going back over the list of keys to perform the actual transactions. Any other ideas? Thanks, Russell. -- Russell Fulton, Computer Center, University of Auckland, New Zealand. <rj_fulton@aukuni.ac.nz>