Re: NATURAL JOIN without join columbs
From: Jon Heggland <heggland_at_idi.ntnu.no>
Date: Fri, 2 Sep 2005 09:01:09 +0200
Message-ID: <MPG.1d82172478021c599896fe_at_news.ntnu.no>
Date: Fri, 2 Sep 2005 09:01:09 +0200
Message-ID: <MPG.1d82172478021c599896fe_at_news.ntnu.no>
In article <g_LRe.349013$5V4.156421_at_pd7tw3no>, toledobythesea_at_oohay.ac
says...
> while there may not be any common 'columns', some people say that there
> is always at least one common attribute, namely the empty set.
Nitpick:
There is always one (and only one) common /set of attributes/ (even if it is empty). That set, of course, is the intersection of the headings of the operands.
-- JonReceived on Fri Sep 02 2005 - 09:01:09 CEST