How To: Perform a direct connect to Oracle without a tnsnames.ora file


Establishing a direct connect connection from ArcGIS to an Oracle instance requires the Oracle client to be present on the machine where the application is performing the connection. In addition, when providing the connection parameters, the user must provide the information that specifies which Oracle instance for the connection.

Historically, the primary method users have used for defining which Oracle instance the connection will reference is by placing the name of an entry from the tnsnames.ora file after the user's password.

Instructions provided describe an example of how to establish a connection without using a reference from the tnsnames.ora file.


To establish a direct connect connection without referencing the Oracle file tnsnames.ora, set the following syntax after the user's password:


For example, in SQL*Plus, to connect to another instance on a machine named HARP and the Oracle sid named geodb, execute the following command:

SQL> CONNECT sde/sde@harp:1521/geodb

With ArcGIS, to connect to the same Oracle instance in the prior example, provide the same parameters after the password, @harp:1521/geodb.