Do keep in mind that querying across databases generally garners really poor performance, and can bring your application to its knees with astonishing speed.
________________________________________ From: pgsql-admin-ow...@postgresql.org [pgsql-admin-ow...@postgresql.org] on behalf of Albe Laurenz [laurenz.a...@wien.gv.at] Sent: Wednesday, October 02, 2013 3:58 AM To: Bhanu Murthy; pgsql-ad...@postgresql.org; pgsql-sql@postgresql.org Subject: Re: [ADMIN] DB link from postgres to Oracle; how to query Dbname.tablename? Bhanu Murthy wrote: > Using Oracle Heterogeneous Services (Oracle HS) I have configured/created a > DB link from Postgres 9.3 > database into Oracle 11gR3 database (with postgres DB user credentials). > > SQL> create public database link pg_link connect to "postgres" identified by > "blahblah" using > 'postgresql'; > Since Postgres does not support public synonyms across databases in a > cluster, how do I connect to a > specific database and query a specific table in this Postgres cluster using > the HS DB link? > > Let's say, if I have 2 Postgres databases named pgdb01 and pgdb02 in the > Postgres cluster, using this > DB link that I have created in Oracle, how can I query a specific table > called table01 from pgdb01 > database? > > Even though the table user_account exists in pgdb01 database, I cannot select > from it using the DB > link. You have to connect to a database to query its data. Rather than defining a database link to database "postgres", define two links, one for "pgdb01" and one for "pgdb02". Yours, Laurenz Albe -- Sent via pgsql-admin mailing list (pgsql-ad...@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin -- Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-sql
