Oracle ORA-12154: TNS: Could not resolve service n

Question

I am a SQL Server user .

I am on a project that is using oracle (which I rarely use) I need to create an ODBC connection so I can access the some data via MS Access I have a application on my machine called oraHome90. It seems to allow a configuration of something called a listener in a “net configuration utility”, I think that a “Local Net Service Name Configuration” needs to also be done. The IT support gave me this information to set up the ODBC connection . I have tried every combination that I can think of. I can get past a test that successfully passes a test to “login“ to the oracle server database. When I try to create the ODBC connection I get the following error: ORA-12154: TNS: Could not resolve service name.

Assuming that I want to start from scratch and the following information is supposed to allow for me to connect to the database….. Any suggestions or comment ? Note: ultimately the project will have a website .ASP page query the data, but I have to first prove that I can see the data using the ODBC connection via MS Access

Service name: SERVICENAME
HOST = HOST.XYZi.com
User Id: MYUSERID
Password: MYPASSWORD
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

'Oracle Connection
Dim ocst
Dim oconn

ocst = "Provider=OraOLEDB.Oracle;" & _ 
        "Data Source=DATASOURCE;" & _ 
        "User ID=CHIJXL;" & _ 
        "Password=password;" 

set oconn = CreateObject("ADODB.Connection")

Answer 1

I had a same problem and the same error was showing up. my TNSNAMES:ORA file was also good to go but apparently there was a problem due to firewall blocking the access. SO a good tip would be to make sure that firewall is not blocking the access to the datasource.

Answer 2

In my case, the error are because I have 2 Oracle clients, It's the solution:

Oracle ORA-12154 error on local IIS, but not with Visual Studio Development Server

Answer 3

I have resolved this issue by removing sqlnet.ora from the C:\oracle\ora92\network\ADMIN path

• Make sure TNSNAMES.ORA file exists in the right directory
• Make sure PATH environment variable is having entry for oracle
• Make sure no syntax issues in the TNSNAMES.ORA
• Try removing sqlnet.ora file

Answer 4

@Warren and @DCookie have covered the solution, one thing to emphasise is the use of tnsping. You can use this to prove your TNSNames is correct before attempting to connect.

Once you have set up tnsnames correctly you could use ODBC or try TOra which will use your native oracle connection. TOra or something similar (TOAD, SQL*Plus etc) will prove invaluable in debugging and improving your SQL.

Last but not least when you eventually connect with ASP.net remember that you can use the Oracle data connection libraries. See Oracle.com for a host of resources.

Answer 5

from http://ora-12154.ora-code.com

ORA-12154: TNS:could not resolve the connect identifier specified
Cause: A connection to a database or other service was requested using a connect identifier, and the connect identifier specified could not be resolved into a connect descriptor using one of the naming methods configured. For example, if the type of connect identifier used was a net service name then the net service name could not be found in a naming method repository, or the repository could not be located or reached.
Action:

• If you are using local naming (TNSNAMES.ORA file):

• Make sure that "TNSNAMES" is listed as one of the values of the NAMES.DIRECTORY_PATH parameter in the Oracle Net profile (SQLNET.ORA)

• Verify that a TNSNAMES.ORA file exists and is in the proper directory and is accessible.

• Check that the net service name used as the connect identifier exists in the TNSNAMES.ORA file.

• Make sure there are no syntax errors anywhere in the TNSNAMES.ORA file. Look for unmatched parentheses or stray characters. Errors in a TNSNAMES.ORA file may make it unusable.

• If you are using directory naming:

• Verify that "LDAP" is listed as one of the values of the NAMES.DIRETORY_PATH parameter in the Oracle Net profile (SQLNET.ORA).

• Verify that the LDAP directory server is up and that it is accessible.

• Verify that the net service name or database name used as the connect identifier is configured in the directory.

• Verify that the default context being used is correct by specifying a fully qualified net service name or a full LDAP DN as the connect identifier

• If you are using easy connect naming:

• Verify that "EZCONNECT" is listed as one of the values of the NAMES.DIRETORY_PATH parameter in the Oracle Net profile (SQLNET.ORA).

• Make sure the host, port and service name specified are correct.

• Try enclosing the connect identifier in quote marks. See the Oracle Net Services Administrators Guide or the Oracle operating system specific guide for more information on naming.

Answer 6

We also had the similar issue. What we found out that we had provided multiple aliases for our connection string in tnsnames.ora, something like:

svc01, svc02=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=xxxx)(port=50))(CONNECT_DATA=(SERVER=DEDICATED)(service_name=yyyysvc.world)))

so when creating a connection using ODBC, when we selected the value for TNS service name, the auto populate was showing 'svc01,' (please note the extra comma there). As soon as we removed the comma, it started working for us.