Re: [SQL] can a column be aliased?

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От darcy@druid.net (D'Arcy J.M. Cain)
Тема Re: [SQL] can a column be aliased?
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Msg-id m0z3f0t-00006FC@druid.net
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Ответ на Re: [SQL] can a column be aliased?  (James Olin Oden <joden@lee.k12.nc.us>)
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Thus spake James Olin Oden
> > Thus spake James Olin Oden
> > > I know this is probably a strange question, but can you give a column
> > > name an alias?  The reason I ask is because I have recently realized I
> >
> > SELECT table1.oid AS custnum, table2.oid AS salesman FROM ...
> >
>
> OK, I get that, but what if you want to say:
>
>    SELECT table1.custnum, table1.name, table2.invoicenum from table1, table2
>
>       WHERE table1.custnum = table2.custnum;
>
> and without using the AS clause table1.custnum is pointing to table1.oid?
> The idea is in perhaps the creation of the table to do something like the AS
> clause, so that I don't have to "know" later that custnum (the key field) is
> actually the oid column.  The end result with this is to hide the
> implementation details of the database from those querying it.  I might be
> really reaching, but it would be nice if something like this is a
> available...james

I don't think so.  Better use a sequence instead.  You shouldn't be
using OID as a key anyway.  You lose the value if you dump and reload.

--
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 424 2871     (DoD#0082)    (eNTP)   |  what's for dinner.

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