Why are version 6 views so sluggish? How to improve?

Neophyte asks...

I support an old version 6 database on a small VAX/VMS machine. I just removed some common logic from several SQL*plus batch jobs and created a view that performed the same logic. The original SQL was then modified to include the view in a join. So... same logic, just implemented differently.

No indexes were changed. Only about 50 rows result from the logic in the view. That view is joined to another rather large table. I was hoping the query engine would evaluate the view and process it once and the results simply stored in a cache.

My run times increased by at least an order of magnitude. Why?

If this database were upgraded to version 7 would it work properly?

Are there ways to tweak the version 6 database so the view was not such a pig?

-- 
Keith W. Johnson, Tektronix, GPID/NWD Info Services, Wilsonville, OR, USA
Internet: keith.w.johnson_at_tek.com  Voice: 503-685-2953  Fax: 503-685-2261