Re: Interesting article: In the Beginning: An RDBMS history
From: Jon Heggland <jon.heggland_at_idi.ntnu.no>
Date: Fri, 07 Apr 2006 21:56:45 +0200
Message-ID: <e16g5q$475$1_at_orkan.itea.ntnu.no>
Date: Fri, 07 Apr 2006 21:56:45 +0200
Message-ID: <e16g5q$475$1_at_orkan.itea.ntnu.no>
dawn wrote:
> Yes, when doing set operations on an ordered set of attributes,
> everything is handled as if the ordering were not there. So, the
> ordering is irrelevant to SQL,
FYI: SQL's set operations are based on attribute ordering. There are variant set operations in the standard that are based on attribute names instead (a CORRESPONDING keyword, IIRC), but I don't know if anyone have implemented them.
-- JonReceived on Fri Apr 07 2006 - 21:56:45 CEST