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.
So the quick answer is no, there is no built-in external table support
in PostgreSQL; normally people load the data using COPY instead.
There's a work in progress on this topic at
http://pgfoundry.org/projects/pgexternaltable/ , but it's extremely
rough at this point and I'm not sure if it's even moving in the right
direction--the main project would do something like this via SQL/MED,
and I don't think that's how the prototype is being built at all.
The only PostgreSQL-based product I'm aware of that has working external
table support already is Greenplum DB.
--
Greg Smith 2ndQuadrant Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com www.2ndQuadrant.com