Subject: TSQL benchmark. Re: Key time-invariance

From: (Fabio Grandi) <[email-masked]>
Date: Tue, 27 Apr 93 12:05:17 +0100

As to the problem of Key time-invariance
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We agree with Jim Clifford on the importance
of the "grouping" issue. Our position can be
summarized as follows:

1) the benchmark model SHOULD support the grouping
   (e.g. via surrogates) and, thus, keys are
   not required to be time-invariant;

-- or, alternatively --

2) if the model does not support the grouping,
   the keys SHOULD be time-invariant, so that
   the user can explicitly support the grouping
   via the key.

However, we prefer the first solution and
strongly disagree with a ungrouped model
together with time-variant keys.

Sincerely,
F. Grandi, M.R. Scalas and P.Tiberio.