Re: foreign data wrappers

Hi,

I managed to clone a copy of 9.1devel and compiled an binary from it. I also did a make in the 'contrib/file_fdw/' folder and a file_fdw.so file is generated.

But the following error occurs when I was trying to experiment with the file FDW:

postgres=# CREATE FUNCTION file_fdw_handler() RETURNS fdw_handler AS 'file_fdw' LANGUAGE C STRICT;
ERROR: could not access file "file_fdw": No such file or directory
STATEMENT: CREATE FUNCTION file_fdw_handler() RETURNS fdw_handler AS 'file_fdw' LANGUAGE C STRICT;
ERROR: could not access file "file_fdw": No such file or directory

Did I miss anything?

ZY

On 26-Mar-2011, at 11:07 PM, Andrew Dunstan wrote:

>
>
> On 03/24/2011 10:07 PM, Zheng Yang wrote:
>>
>>
>> I've briefly gone through the slides. Regarding the 6 callbacks, is that correct to say that a full table scan will always be performed irregardless of the sql statement,
>> the FDW is blind to the sql query performed, right?
>
> Yes, fairly much. If the feed is large you need some way to pass a limit to the foreign side, possibly via table options. I'm fairly sure you won't be able to get it via the SELECT statement.
>
>>
>> And can anyone help explain what a planner is? What does this "provide cost estimates to planner" mean? Thanks!
>
>
> See <http://www.postgresql.org/docs/current/static/planner-optimizer.html>
>
> If you're going to work on PostgreSQL code you need to read the docs.
>
> cheers
>
> andrew
>