How to use existed tns connection for new one?

* The key point is 'Using' keyword that checks tnsnames.ora connection node then you can reach remote database.

SQL> CREATE DATABASE LINK "ALPER_DATABASE_NEW_LINK"
 CONNECT TO hr
 IDENTIFIED BY hr
 USING 'ALPER_DB';

SQL> CREATE DATABASE LINK "ALPER_DATABASE_NEW_LINK2"
 CONNECT TO hr
 IDENTIFIED BY hr
 USING 'ALPER_DB';

SQL> CREATE DATABASE LINK "ALPER_DATABASE_NEW_LINK3"
 CONNECT TO hr
 IDENTIFIED BY hr
 USING 'ALPER_DB';