Oracle Database Administration I — Question 118

Which statement is true about database links?

Answer options

• A. Private database link creation requires the same user to exist in both the local and the remote databases.
• B. A database link created in a database allows a connection from that database's instance to the target database's instance, but not vice versa.
• C. A public database link can be used by a user connected to the local database instance to connect to any schema in the remote database instance.
• D. A public database link can be created only by SYS.
• E. A database link can be created only between two Oracle databases.

Correct answer: B

Explanation

The correct statement is B because a database link allows one-way connectivity from the local database to the remote one, but not the reverse. Option A is incorrect since a private link does not require the same user in both databases. Option C is inaccurate as a public link's access is determined by privileges, not universal accessibility to any schema. Option D is wrong since public database links can be created by users with proper privileges, not just SYS. Option E is misleading as database links are primarily associated with Oracle databases, but other database types can be linked with appropriate configurations.