Remote database connections

Establishing a connection remotely means running the SQL command-line utility on a different host other than the Oracle Database 11g XE machine and initiating a database connection command using the valid database credentials over the network using a connect string.

The following screenshot is taken from Oracle Database 11g XE on Windows, and demonstrates establishing a remote database connection to the database:

As discussed earlier, a connect string defines which database server to connect to, on what port, and using what protocol. In the preceding example, xe is the name of the connect string.

Alternatively, we can connect to the database by providing the database host name and port as shown in the following screenshot:

The database hostname name and port information is basically encapsulated in the connect string.

Using the local sqlplus utility we can connect to the database via listener; thus, simulating remote client connections. To achieve this, we need to configure the tnsnames.ora file and make sure that the listener is running.

The remote host initiating database connection should have Oracle Client software installed. It is through this client software that the Oracle command-line utilities connect to the database.

You can download Oracle Database 11g R2 Client software for Windows from http://www.oracle.com/technetwork/database/enterprise-edition/downloads/112010-win32soft-098987.html. To download the software you have to log in and accept the license agreement.