In article <bdf69bdf.0210031023.375229d8_at_posting.google.com>,
Mikito Harakiri <mikharakiri_at_yahoo.com> wrote:
>
>It is often emphasized how beatuful relational theory is, because it
>is based on the set theory. While there is undoubtedly some
>connections, but may I ask why set union is a basic relational
>operator, and intersection is not? (Intersection could be expressed
>via combination of join and projection).
Why do you ask questions and then put the answer right behind it in
brackets? :-)
Received on Fri Oct 04 2002 - 08:04:40 CDT
