MultiShardConnection should inherit from System.Data.Common.DbConnection

My code needs to run in both environments: single database and multishard databases. I need an ease way to manipulate between MultiShardConnection and SqlConnection, between MultiShardCommand and SqlCommand and so on. I would be very gratefull if MultiShardConnection class whould inherit from System.Data.Common.DbConnection class. That would make possible for me to operate on abstract classes from System.Data.Common namespace instead of specific implementation either MultiShardConnection or SqlConnection.

Start by locating MultiShardConnection and the related MultiShardCommand classes, then compare their public contracts with System.Data.Common.DbConnection and the corresponding ADO.NET abstractions. Check how the single-database and multishard types are currently used; the work is done when the requested common abstraction can support both environments without breaking existing APIs.

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