Set up the tnsnames.ora file

The tnsnames.ora file contains information needed to connect to the Oracle servers.

the TNS_ADMIN environment variable points to the location of the tnsnames.ora file. It is recommended that this is held in the same directory as the Oracle Client / ODBC Driver (d:\Oracle_Client in our example).
you may need the assistance of an Oracle specialist to help with the setup of your tnsnames.ora file
when an Oracle server is configured, a tnsnames.ora file is created in the Oracle directory structure. You may wish to locate this file and use this.
For our system, the location for this is: d:\oraclexe\app\oracle\product\11.2.0\server\network\ADMIN

Example of a tnsnames.ora file

The following shows the contents of a tnsnames.ora file. The first entry defines the connection information to database XE. There can be multiple entries such as these if you wish to connect to multiple databases.

XE =

(DESCRIPTION =

(ADDRESS = (PROTOCOL = TCP)(HOST = ORASERV)(PORT = 1521))

(CONNECT_DATA =

(SERVER = DEDICATED)

(SERVICE_NAME = XE)

)

EXTPROC_CONNECTION_DATA =

(DESCRIPTION =

(ADDRESS_LIST =

(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))

)

(CONNECT_DATA =

(SID = PLSExtProc)

(PRESENTATION = RO)

)

ORACLR_CONNECTION_DATA =

(DESCRIPTION =

(ADDRESS_LIST =

(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))

)

(CONNECT_DATA =

(SID = CLRExtProc)

(PRESENTATION = RO)

)

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