Re: Creating unique or "internal-use-only" column names (ColumnRef)

Peter Moser wrote:
> Good afternoon,
> is it possible to create unique column names or to give column names inside
> the parser phase that do not interfer with the outside world, i.e. with
> column names from tables or aliases given by the user.
>
> Some short background:
> I created my own from-clause-item, that gets rewritten into a sub-query. I
> do this because I want to re-use existing code as much as possible. The
> rewritten sub-query gets transformed with "transformRangeSubselect"...
> Within this sub-query I need 3 columns that shouldn't interfer with columns
> from the input. We refer to them from a JOIN-ON clause and an ORDER-BY
> clause.

This seems pretty much the same as a junk attribute, if I understand you
correctly. I suggest given a look at how those work.

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Álvaro Herrera http://www.2ndQuadrant.com/
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