RE: Optimized Search method for DB files. ?

[Buck Calabro <mcalabro@xxxxxxxxxxxx>]

On Thursday, October 22, 1998 1:29 PM, Ravi [SMTP:ravi@spacestar.com] 
wrote:
> Prabhu.Chella@smed.com wrote:
> >
> > Actually we have a plan to introduce a concept, wherein the DB might
> > contain data from more than one company in the same AS/400 DB.
> > Say,     If the DB of each Company had Employee first name, last name
> > .......   Now it would have an additional
> > field(1'st key field in all the DB's) which will determine to which
> > company
> > the data belongs to .
-snip-
> > Thanks in Advance ,
> > Chellaprabhu.
>
> Instead of combining data from multiple companies into the same file,
> have you considered using multiple members? (ie) A member for each
> company. Depending on the company you want to work with, a CL can set up
> appropriate overrides.
>
> Ravi

As someone who works with multi-member files daily, I would caution 
against their use for several reasons:
1) Not compatible with SQL
2) Not compatible with ODBC
3) Not compatible with other database systems
4) Inability to query across members

Without knowing about the applications that will access this database, 
it's hard to propose a design for a search method.  I think the main thing 
to keep in mind is to create an access path for each method you require 
(within reason.)  That way, CHAIN can return the individual records you 
need, SETLL/READE can return the subset of records you need, SQL can do 
set-at-a-time updates, etc.

Buck Calabro
Commsoft, Albany, NY
mailto:mcalabro@commsoft.net

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