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From: kilgallen@eisner.decus.org (Larry Kilgallen)
Subject: Re: Looking for Indexed Sequential File Package
Date: 1997/07/16
Message-ID: <1997Jul16.140050.1@eisner>#1/1
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References: <33CCA95E.167EB0E7@avions.aerospatiale.fr>
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Date: 1997-07-16T00:00:00+00:00
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In article <33CCA95E.167EB0E7@avions.aerospatiale.fr>, Paul CHARDON <paul.chardon@avions.aerospatiale.fr> writes:

> 	A friend of mine is lookink for a reusable Ada83 component to manage
> indexed sequential files. This package must give a quick access to a
> file of item (record). It could give access to those record sorted
> according to one or more keys (those keys are primary or secondary keys
> that are fields in the record).

If by "reusable" you mean portable to any Ada83 environment,
I do not believe it is possible to meet the "must give quick
access" requirement.  What must be done to achieve performance
goals varies quite a bit between operating systems.

You do not mention any reliability requirement, but if I were
in the market for such a thing I would likely be quite concerned
about ensuring that a write-through caching strategy was used.
Achieving that is beyond the control of the Ada environment,
and not going to be automatic if the operating systems involved
are Windows NT or Unix.

Larry Kilgallen