Missing db.client.operation.duration Metric for Oracle, MongoDB, Redis in .NET Agent

[deepakkumar11]

In the OpenTelemetry .Net Agent, we have observed that metrics for database call durations—specifically db.client.operation.duration metric—are not being generated for most SQL and NoSQL operations
Upon reviewing the code for the oracle instrumentation module, we did not find any implementation that emits this metric. It appears that db.client.operation.duration is not currently supported in the oracle plugin or similar instrumentation modules for NoSQL clients like mongo db, redis etc.
Could you please clarify why this metric is not generated for oracle etc? Is there any plan to add support for db.client.operation.duration in future releases of the OpenTelemetry Dotnet Agent for Oracle and other db libraries?

[martincostello]

Implementation is typically driven by the needs of the community and from members of the community contributing support for areas where support is lacking. The most popular choices typically get implemented sooner than later, if at all.

Such functionality is typically part of a library produced from the open-telemetry/opentelemetry-dotnet-contrib repository. For example, that's where SQL Server support for metrics exists. The Redis library doesn't have support for metrics yet, as you've found.

In some cases, such as for PostgreSQL, the support is built-into the database provider itself.

The MongoDB driver doesn't seem to have built-in support for OpenTelemetry metrics and we don't currently have a contrib package either.

As far as I'm aware, the Oracle provider is closed-source, so Oracle themselves would need to add OpenTelemetry support to it. I've never worked with Oracle DBMS myself, so I don't know whether or not a contrib package to extend it could be built.

In summary, the metrics aren't generated because no one has done the work to do so. I'm not aware of any active decisions to not implement them, it's just that someone in the community hasn't stepped up to do so.