"Aggregate" operators

From: Erwin <e.smout_at_myonline.be>
Date: Mon, 24 Apr 2017 11:06:39 -0700 (PDT)
Message-ID: <37fcaeb7-36f2-44fb-bd07-39e371434d1f_at_googlegroups.com>

[Quoted] [Quoted] Looking for a *formal* definition of the term "aggregate" operator.

[Quoted] [Quoted] The term is quite familiar and the one in common use to denote SQL operators such as MIN, MAX, AVG that occur exclusively in connection with some GROUP BY.

However, "occur exclusively in connection with SQL GROUP BY" is rather non-mathematical as a formal definition and so, is anyone around here aware of something more rigorous as a *definition* of when some operator is or is not an "aggregate" operator ? Received on Mon Apr 24 2017 - 20:06:39 CEST