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11-02-2016, 02:12 PM
Post: #6
One of the challenges that we faced with these commands was trying to determine if they should follow the "mathematical definition" or the "programming definition". What I mean by this is that the purely mathematical definition operates exclusively on sets - groups with no duplicates. However, in actual usage there are tons of cases where you actually DO want to keep duplicates and not be suppressing them all. Having the pure set based version means that in probably the majority of cases a user would like to use it in a program, they end up having to rewrite it to get the desired behavior.

The compromise we decided to make was that if you do want to suppress duplicates, the UNION command would do so as has been pointed out.


Although I work for HP, the views and opinions I post here are my own.
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Messages In This Thread
INTERSECT ? - Tyann - 10-28-2016, 03:26 PM
RE: INTERSECT ? - compsystems - 10-28-2016, 03:45 PM
RE: INTERSECT ? - compsystems - 10-28-2016, 08:00 PM
RE: INTERSECT ? - parisse - 10-29-2016, 06:24 AM
RE: INTERSECT ? - Tyann - 11-01-2016, 04:35 PM
RE: INTERSECT ? - compsystems - 11-03-2016, 11:01 AM
RE: INTERSECT ? - Tim Wessman - 11-02-2016 02:12 PM
RE: INTERSECT ? - Tyann - 11-03-2016, 05:34 AM

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