Fixing the Oracle Connection Error: ORA-12154: TNS:could not resolve the connect identifier specified
To fix this error when connecting to an Oracle database, follow the steps below:
1. Create the tnsnames.ora file
Create a file named tnsnames.ora with the following content:
REALDB =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = YOUR_IP_OR_HOST)(PORT = YOUR_PORT))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = YOUR_SERVICE_NAME)
)
)
Replace YOUR_IP_OR_HOST, YOUR_PORT, and YOUR_SERVICE_NAME with the actual connection details.
2. Save it to the correct directory
Save the file to the following path:
C:\instantclient_19_6\network\admin
If the network and admin folders do not exist, create them manually.
3. Set environment variables in Windows
Go to:
Control Panel → System → Advanced system settings → Environment Variables
Add or edit the following System Variables:
Add or edit the following environment variables:
- TNS_ADMIN
Name:TNS_ADMIN
ValueC:\instantclient_19_6\network\admin - ORACLE_HOME
Name:ORACLE_HOME
Vakue:C:\instantclient_19_6
4. Edit the Apache configuration
Open the file:
C:\Program Files\NetMake\v9-php81\components\apache\conf\httpd.conf
Add the following lines:
FcgidInitialEnv TNS_ADMIN "C:/instantclient_19_6/network/admin"
FcgidInitialEnv ORACLE_HOME "C:/instantclient_19_6"
These lines should be inserted between the FcgidMaxRequestLen and Timeout directives.
5. Apply the environment setup
- Save the httpd.conf file after adding the FcgidInitialEnv variables.
- Restart your computer so the environment variables (TNS_ADMIN and ORACLE_HOME) are correctly applied.
6. Create the connection in Scriptcase
- pen Scriptcase and go to the database connection creation screen.
- Select the desired Oracle driver.
- In the "Database" field, enter the name defined in the tnsnames.ora file (e.g., REALDB).
If everything is configured correctly, the connection to the Oracle database will be established successfully.