RE: Accessing files In QTEMP

[Buck Calabro <buck.calabro@xxxxxxxxxxxxxxxxx>]

Joel Fritz wrote:

>OTOH, if you don't have any SQL 
>tools available except QMQRY, and 
>all your database work has to be 
>done in RPG, the only problem is 
>keeping the file overrides and 
>logical members straight.

I have great experience with multi-membered files, and I respectfully
disagree.  The greatest of all the multi-member problems is that the record
does not know who it "belongs to."  The member knows.  Take the example
where the member segregates data by user.  You can't readily run an RPG
program over one of the members and tell what user the records are for.
Sure, you can use the INFDS to get the member name, but it gets worse.

Imagine that your user IDs are 'intelligent' - they somehow have the user's
location embedded, say CHIBUCK,  NYCJOEL.  Run a report including records
from all the users in NYC.  This situation is contrived, but it is really
bad when you keep financials separated by member; JAN, FEB, MAR or Q11998,
Q21998 or FY1998, FY1999, etc.  Running a report that crosses members is not
fun, especially when you have to select a subset of those members.

It is FAR easier to create those reports if all the data is in one member,
and properly identified by a field in the record.  Going the multi-member
route seems slick, but you'll regret that choice when (not if!) your
business rules change.  That is why database normalisation is a Good Thing -
it makes changes easier to deal with.  That is why multi-members  are not
SQL compliant - they violate the basic concept of proper database
normalisation.  It is exactly synonymous to segregating the data by file,
library or physical machine - one of the attributes of the record is not in
the record itself.

Buck Calabro
Aptis; Albany, NY
"We are what we repeatedly do.
 Excellence, then, is not an act, but a habit." --Aristotle


Billing Concepts Corp., a NASDAQ Listed Company, Symbol: BILL
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