Oracle TNS Names - Quiz Explanation

The correct answers are indicated below, along with text that explains the correct answers.

1.	The tnsnames.ora file is best described as Please select the best answer.
	A.	A process that listens for incoming database connections
	B.	A file that is used to supply host, protocol, and database information for incoming requests
	C.	A file that is used to hide the details about what is needed to connect to a remote database
	D.	Total Network Support
	The correct answer is C. The tnsnames.ora file is best described as a file that is used to hide the details about what is needed to connect to a remote database. It "pairs" the service name with the host name, the protocol, and the database name. A is incorrect because the listener process, not the tnsnames.ora file, listens for connections. B is incorrect because the tnsnames.ora file is used for outgoing requests, not incoming requests.

2.	If you were exploring a new Oracle Net Services computer and you did not know if it was configured as an Oracle server, what file would you look for? Please select the best answer.
	A.	tnsnames.ora
	B.	sqlnet.ora
	C.	listener.ora
	D.	protocol.ora
	The correct answer is C. If you were exploring a new Oracle Net Services computer and you did not know if it was configured as an Oracle server, you would look for the listener.ora file. An Oracle server must have a listener process defined in order to be considered a Oracle Net Services server. A, B, and D are incorrect because the tnsnames.ora, sqlnet.ora, and protocol.ora files are only used by Oracle Net Services clients.

3.	Which of the following best describes a database link? Please select the best answer.
	A.	A software component that assists in establishing connectivity with remote servers
	B.	An internal Oracle component that adds a USER ID and password to a TNS service name
	C.	A component that makes the physical connections to the Oracle database, establishing a server process
	D.	A tool to define the Oracle Net Services environmental files
	The correct answer is B. A database link can best be described as an internal Oracle component that adds a USER ID and password to a TNS service name. Database links are stored in the Oracle dictionary. They consist of the link name, the TNS name, the user ID, and the password. A is incorrect because a database link is not software, it is an entry in the Oracle dictionary. C is incorrect because database links do not make database connection, this is done by the listener process. D is incorrect because database links do not define environments.

4.	The main shortcoming of SQL*Net version 1 is that Please select the best answer.
	A.	It does not have the ability to establish communications between multiple protocols.
	B.	It does not possess a listener process.
	C.	It does not have the ability to use connect strings.
	D.	It is a legacy technology.
	The correct answer is A. The main shortcoming of SQLNet version 1 is that it does not have the ability to establish communications between multiple protocols. SQLNet version 2 has corrected this by supporting multiprotocol "communities." B is incorrect because SQLNet version 1 uses a listener called ORASRV. C is incorrect because SQLNet version 1 does use connect strings.

5.	Which of the following components is not used by the Oracle listener? Please select the best answer.
	A.	listener.ora
	B.	tnsnames.ora
	C.	database link information
	D.	dispatcher process
	The correct answer is B. The tnsnames.ora file is not used by the Oracle listener. The tnsnames.ora file is only used by the remote client, and not the receiving server. A is incorrect because the listener.ora file is used by the listener at start-up time. C is incorrect because database link information is used by the listener to get the TNS service name. D is incorrect because the dispatcher processes are used by the listener to channel incoming database requests.