Query grain state from storage

[gschuager]

I have several grains with GUID ids that persist state to the OrleansStorage table using the ADO.NET provider.
I am wondering how can I locate the row corresponding to a given grain based on its type and id... I see the grainidhash, grainidn0, grainidn1 and grainidextension columns but I couldn't find any docs related to how to map a given GUID to this columns for querying.

[gfix]

You can see how the Guid is transformed into GrainIdN0, GrainIdN1 and GrainIdExtension here. The GrainIdHash is created here.