Re: postgres external table

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