You just use a view. Period.
CREATE VIEW foobarview AS SELECT a, c FROM foo;
What else do you need?
CREATE VIEW foobarview AS SELECT a*2 AS double, b*c AS multiple,
max(a,c) AS maximum FROM foo;
I believe views does it all.
/Roger
Eliel Mamousette wrote:
>
> "Tom Lane" <sss.pgh.pa.us> writes:
> > "Eliel Mamousette" <eliel@panix.com> writes:
> [question re: returning rows deleted to conserve bits]
> >
> > You don't specify more than one return type --- you specify one return
> > type that is a composite type. Composite types are currently tied to
> > tables; creating a table also creates a type that represents one of its
> > rows. Thus
> >
> > create table foo (a int, b int, c int);
> > create function foobar (...) returns foo as ...
>
> Does rule also apply to views?
>
> For example, what is the best practice when one doesn't want to return
> a whole row? Given the restriction as stated, if I only wanted to
> return column a and c from the table above, would I create a view
> fooview and then say that function foobarview returns fooview?
>
> If I write a paragraph about this process, to whom should I mail it for
> inclusion in the documentation? I imagine it will be a FAQ for we who
> are striving to escape from the legacy of Sybase and Microsoft's SQL
> Server....
>
> > Note that there are some annoying syntactic limitations on what you can
> > actually *do* with a function returning tuples. We have plans to
> > improve that situation in 7.2 or beyond, but for now, this facility
> > isn't nearly as useful as one might think.
>
> Thanks Tom, but can you be a bit more specific about what one can't do
> with returned tuples? It might save some folks (and me) some time.
>
> thanks again, this process has been extremely helpful,
> eliel
>
> > regards, tom lane
> >
>
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