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Theta join or equijoins??

JS
What is the definition of a theta join? I read that all joins with the
comparison operators:

=, <,> etc. are theta joins, but joins with = are called equijoins. How can
a theta join both be equijoin and a theta join?
Jul 23 '05 #1
1 8227
In Relational Algebra a Theta Join is a join based on any of the binary
comparison operators (=, <, <=, >=, >, <>). An Equi-join is one example of a
Theta Join. There is no contradiction.

--
David Portas
SQL Server MVP
--
Jul 23 '05 #2

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