Re: postgres external table

Greg Smith <greg@2ndquadrant.com> writes:
> Craig Ringer wrote:
>> For those non-Oracle users among us, what's an external table?

> External tables let you map a text file directly to a table without
> explicitly loading it.  In PostgreSQL, if you have data in a CSV file,
> usually you'd import it with COPY before you'd use it.  If external
> tables were available, you'd just say there's an external table as a CSV
> file and you could start running queries against it.

I'm finding it hard to visualize a use-case for that.  We must postulate
that the table is so big that you don't want to import it, and yet you
don't feel a need to have any index on it.  Which among other things
implies that every query will seqscan the whole table.  Where's the
savings?

            regards, tom lane