Database link Ora-12154:tns: Unable to resolve the specified connection identifier

Ora-12154:tns When creating database link: The specified connection identifier could not be resolved.

The error is as follows:

Find a lot of information on the Internet, and found that they have been using the service name above the client, should use the service name on the server.

Dblink is a communication between two Oracle database servers, you must not write the service name on the client's Tnsnames.ora when you create Dblink, and today you have made a silly question. Remember.

Be sure that the service name you built in database a dblink is on the a machine, not on the client of the non-database server. If you are creating a database on a client landing, do not use the service name on that client.

Thank you: http://www.itpub.net/thread-19368-1-1.html

It is also important to note that if you create a database user with a password that is a pure number, you need to add double quotes instead of a pure number.

Create DATABASE link Testlink 
connect to TEST identified by "1"