Re: COPY Transform support

Dimitri Fontaine <dfontaine(at)hi-media(dot)com> writes:
> Le mardi 08 avril 2008, Tom Lane a crit:
>> That's sufficiently covered by the proposal to allow a COPY FROM as a
>> table source within SELECT, no?

> Well, yes, the table source has text as datatypes and the select expression on
> the column will call whatever function/cast etc to do the work. But that
> opens the door to second class citizen storage solution for PostgreSQL, by
> letting the user CREATE VIEW atop of it:

[ shrug... ] I don't actually have a problem with that. If we did want
to prohibit that, we'd have to somehow prohibit SRFs from reading files,
because you can do it today with any untrusted PL.

I note also that presumably COPY FROM 'file' would still be restricted
to superusers, and only COPY FROM STDIN would be available to those
without a license to shoot themselves in the foot. So the opportunity
to do anything view-like would be restricted to adults(?) anyhow.

(One of the issues that'd have to be addressed to allow a table source
syntax is whether it's sane to allow multiple COPY FROM STDIN in a
single query. If so, how does it work; if not, how do we prevent it?)

regards, tom lane