Table/Column Definition Question

I'm defining Oracle tables that match our existing IMS segments (don't bother discussing reengineering - we've been down that road, don't have the time, staff, etc. - let's just say it's a given that we're doing this this way) for migration.
We will be moving the data into our existing cobol copy code layout because we will probably be running our existing programs for a long time. So - the level of breakdown of fields (redefines, etc.) will be available there.
Eventually, I have to believe that we will be accessing Oracle via other methods than cobol.

Can anyone give me some feel for the best way to define this stuff to Oracle? Specifically, I am struggling with the level of detail. For example (1 of many) I have a general ledger number of 20. Made up of 8 parts. or 9 if I go down to subdept. So do I define one column of 20 char or 8 pieces? What are the pros and cons I should be considering to make this decision?

If I use views to 'redefine' the look - then if I use a function in the view (to string columns together maybe) then I can't update using the view? Right?

Thanks for any direction here.

Barb. Received on Thu Oct 03 1996 - 00:00:00 CEST