custom probe query after enabling CAP_FORCE_CONNECTION_VERIFICATION

[xsgao-github]

About You:
Name: Song Gao
Company: Starburst Data

Your question:
We are using the Trino JDBC driver and enabled CAP_FORCE_CONNECTION_VERIFICATION in our connector per this doc:

CAP_FORCE_CONNECTION_VERIFICATION	Set to ‘yes’ to verify connection status during initial connection by running a probe query. Available in Tableau 2022.2 and newer.

Now I see Tableau always sends a query select version() during connection.

My questions are:

1. Where is this probe query defined?
2. Can I customize this query or even add a function to validate the returned resultset of the probe query?

[rosswbrown]

The current design of CAP_FORCE_CONNECTION_VERIFICATION does not check the result of the probe query beyond that it does not fail. The probe query should always SELECT 1 for a connector built from the SDK. The probe query is also used to test lifetime and disconnect scenarios as well.

What is your desired use case with a potential customization?

[xsgao-github]

My bad. The probe query is SELECT 1.

I would like to add some validation on Tableau connector. For example, if the server does not meet the minimum version of server requirement, error it out.

[rosswbrown]

Ok, that makes sense. Please open an issue about your desire to enforce the minimum server version as a part of defining a connector. Anything like this would be decoupled from CAP_FORCE_CONNECTION_VERIFICATION.

I'll make sure it gets tagged as a potential enhancement. Thanks.

[xsgao-github]

Feature request here #1210