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黑中国人
New Member

Data Source Credentials

 Data Source Credentials

35257.jpg

Error on establishing connection with credentials.

 

user credentials are accurate and gateway also updated

 

Failed to update data source credentials: Oracle: ORA-12154: Cannot connect to database. Cannot find alias **** in DataSources, , EZConnect. https://docs.oracle.com/error-help/db/ora-12154/Hide details

Status code: 400

 

I also noticed i can't create a new connection with my on premises gateway (personal) as that option is grayed out.

35260.jpg

 

New workspaces or reports also don't recognise the gateway except legacy workspaces or reports

6 REPLIES 6
v-saisrao-msft
Community Support
Community Support

Hi @黑中国人,

Have you had a chance to review the solution shared by @Shai_Karmani @GilbertQ ? If the issue persists, feel free to reply so we can help further.

 

Thank you.

I have reviewed their solutions but i am not connecting through the TNS as such non of the solutions have been able to help me especially with new reports that donot recognize the Gateway meanwhile legacy reports recognize the gateway

_0-1785756918505.png_1-1785757031353.png

 

Hi @黑中国人,

Thank you @Shai_Karmani ,@GilbertQ, for your insights.

The Power BI Oracle documentation says that Personal data gateways don't support updated Oracle connections. Existing Oracle semantic models will continue to work, but new Oracle semantic models require an Enterprise on-premises gateway. If your Oracle database is on-premises, you can move to an Enterprise gateway and recreate the Oracle connection. Note: This upgrade is irreversible, and the semantic model can't be switched back to a Personal Gateway.

Connect to an Oracle Database with Power BI Desktop - Power BI | Microsoft Learn

Data refresh in Power BI - Power BI | Microsoft Learn

 

Thank you.

GilbertQ
Super User
Super User

Hi @黑中国人 

 

There is a long place where I explain how to get this set up for an Oracle database system. https://www.fourmoo.com/2017/04/26/power-bi-on-premise-gateway-configuration-steps-to-an-oracle-data... 





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Shai_Karmani
Super User
Super User

The ORA-12154 is coming from Oracle's client, not from Power BI itself, and it means the alias in your data source cannot be resolved. That usually happens when the Oracle client is not installed on the gateway machine, tnsnames.ora is missing the entry, or TNS_ADMIN is not pointing to the folder holding tnsnames.ora for the account running the gateway service. A quick way to isolate this is to switch the connection to a full EZCONNECT form like host:port/service_name, which bypasses tnsnames.ora and tells you right away whether the client itself is the problem.

 

The grayed-out gateway option is a separate limitation. Personal mode gateways cannot be used to create the centralized connections that new V2 and Fabric enabled workspaces rely on, so they will not appear as a choice there. Install the on-premises data gateway in standard mode from powerbi.microsoft.com/en-us/gateway and register it, and it will show up in the newer workspaces so you can define the Oracle connection there.

 

If this helped, a thumbs up and accepting the solution would be appreciated.

 

Best,
Shai Karmani

I'm not connecting with the tns but with EZconnect. It's been working fine until I recently got this challenge. 

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