-----Original Message----- From: Tom Lane [mailto:t...@sss.pgh.pa.us] Sent: Thursday, December 31, 2015 3:36 PM To: Paragon Corporation <l...@pcorp.us> Cc: pgsql-hackers@postgresql.org Subject: Re: [HACKERS] IMPORT FOREIGN SCHEMA return create foreign table commands are those further filtered in LIMIT and EXCEPT cases?
"Paragon Corporation" <l...@pcorp.us> writes: >> I've implemented IMPORT FOREIGN SCHEMA support for an fdw called >> ogr_fdw against the PostgreSQL 9.5RC1 code base. >> Code is here: https://github.com/robe2/pgsql-ogr-fdw >> It works great except in the Case of LIMIT TO clause (and possible >> EXCEPT though I have to retest EXCEPT to see if there is a case it doesn't work). >> In LIMIT case sometimes works and it sometimes doesn't and when it >> doesn't no foreign tables are created. > Case-folding issue, perhaps? Are you taking care to double-quote the table names in the generated CREATE FOREIGN TABLE statements? Because if you don't, they'll be smashed to lower case and then won't match the quoted table names in your > example. > regards, tom lane Tom, Yes using quote identifier etc. I just rewrote my logic to go by the resulting table name instead of the remote data source name and that seems to do the trick. So I now write: IMPORT FOREIGN SCHEMA ogr_all LIMIT TO(orders, products) FROM SERVER northwind INTO northwind; But with the laundering options off, I would do this: IMPORT FOREIGN SCHEMA ogr_all LIMIT TO("Orders", "Products") FROM SERVER northwind INTO northwind OPTIONS(launder_table_names 'false', launder_column_names 'false') ; So I am guessing you guys are filtering the list so that it works for all FDWs even if the FDW author doesn't directly handle LIMIT / EXCEPT clause? But not sure where that is being done. So instead of doing this check in my code (which is what I was doing) Relname = layer_name (where in my case layer_name is the remote datasource which can be pretty crazy for spatial data like web service layers ) I'm doing this Relname = table_name In the case where laundering is on which is the default table_name != layer_name. In case where user chooses to preserve layer name then table_name == layer_name Thanks, Regina -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers