While I don't see the syntax of:
update table set (col...) = ( val...)
as valuable compared to separate col=val assignments, I do see a value
in allowing subqueries in such assignments:
update table set (col...) = ( select val ..)
Without it, you have to do separate subquery statements, and if they are
complex, that is a waste. I assume that was the motivation for the
feature.
---------------------------------------------------------------------------
Dave Cramer wrote:
> Patrick,
>
> No, they support the syntax:
>
> update table set (col1, col2, col3) = ( val1, val2, val3 )
>
> I have a customer with a rather large application which uses this
> syntax, because they were using informix. There is also a rather
> interesting 4GL project called aubit which is on sourceforge. They would
> also like to see this supported for the same reasons.
>
> Dave
>
>
> On Wed, 2003-02-19 at 15:02, Patrick Welche wrote:
> > > I have a large customer who is converting from informix to postgres and
> > > they have made extensive use of
> > >
> > > update table set (col...) = ( val...)
> > >
> > > as a first pass would it be possible to translate this in the parser to
> > >
> > > update table set col=val
> > >
> > > It would appear that this is SQL3 compliant
> > >
> > > <set clause> ::=
> > > <update target> <equals operator> <row value designator>
> > >
> > > <update target> ::=
> > > <object column>
> > > | <left paren> <object column list> <right paren>
> > >
> > >
> > > or can someone think of another way?
> >
> > I don't understand the original problem. What does informix give you? A
> > text file full of "update table set ()=()" which you then try to feed
> > into postgres? In that case, why not pass said text file through a sed or
> > perl script first?
> >
> > Cheers,
> >
> > Patrick
> --
> Dave Cramer <dave@fastcrypt.com>
> Cramer Consulting
>
>
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