В письме от 26 мая 2016 10:05:56 пользователь Tom Lane написал:
> > 2. I think expression with USING in it is more human readable:
> > CREATE INDEX (xxx op_yyy);
> > is less sensible then
> > CREATE INDEX (xxx USING op_yyy);
>
> Yes. If we were working in a green field, it would have been better to
> make USING (or some other reserved word) required, not optional, there.
> That would have been better for readability and would have avoided some
> syntactic headaches, such as the need to parenthesize the expressions in
> expression indexes. However, we're about 18 years too late to make that
> decision. Opclass with no introductory keyword is the entrenched standard
> at this point, and we're never going to be able to remove it.
No, but we cat keep "USING" as an optional keyword there as it were, just
mention it in the docs. It seems logical to me.
// Actually I did not expected any discussion for this case. Documentations
missed an optional keyword, documentation should be fixed. I am surprised that
there can be any other opinions ;-)
--
Nikolay Shaplov
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