Re: constraints in algebra instead of calculus

Vadim Tropashko wrote:
> R <AND> (R RENAME B as B') )
> IS
> R WHERE B = B'
>
> where the "IS" symbol is relational equality. Relational equality (aka
> "IS") provides a succinct way to say that the symmetric difference of
> the relations
>
> R <AND> (R RENAME B as B') )
>
> and
>
> R WHERE B = B'
>
> is empty.

Forgive me if I'm not paying attention, but why do you need a special symbol and explanation for relational equality? Why can't you just use =?

-- 
Jon