Oracle Database Link

This is how I create a database link or dblink in Oracle. Using the following format, be sure to use the host name or use an IP address of the desired database server. This is the best way to insure it will connect. You need to update the text in RED to your specific environment.

CREATE PUBLIC DATABASE LINK NAME.DOMAIN.COM
CONNECT TO USERID
IDENTIFIED BY PASSWORD
USING '(description=(address=(protocol=TCP)
(host=hostdb_server.com)(port=1521))
(connect_data=(sid=SID)))'
/

The domain.com should match your db_domain parameter and is required if this parameter is set.
SQL> show parameters db_domain
NAME TYPE VALUE
------------- --------- ------------
db_domain string domain.com