RE: SQL, Logical Files, Unions & Indexes.

From: BirgittaHauser

Instead of using joined logical files, you should create SQL views
instead.
Views are much more powerfull than DDS described logical files.

Let's be careful here.  MOST of the time views are a better alternative than
logical files (although logical files can act as both index and view).  In
fact, for most cases you should really consider using DDL to describe all of
your files, including physicals, because of the benefits of DDL.  But this
is different than SQL.

And with the right indexing strategie SQL performs much better than native
I/O even if you are only working with DDS described physical and logical
files.

And here you must be very careful.  SQL performs better than native I/O for
many queries, but it definitely does NOT perform better for single record
reads, writes or updates.

Joe