avoid anonymous caching

[vadv]

closes #67

need fix for tests:

      Unhandled exception. System.Exception: Received unexpected backend message ParseComplete. Please file a bug.
         at Npgsql.Internal.NpgsqlConnector.UnexpectedMessageReceived(BackendMessageCode received)
         at Npgsql.NpgsqlDataReader.<ProcessMessage>g__HandleUncommon|54_0(IBackendMessage msg)
         at Npgsql.NpgsqlDataReader.ProcessMessage(IBackendMessage msg)
         at Npgsql.NpgsqlDataReader.TryRead()
         at Npgsql.NpgsqlDataReader.ReadAsync(CancellationToken cancellationToken)
         at Program.<Main>$(String[] args) in /workspace/tests/dotnet/prj/anon_queries/Program.cs:line 23
         at Program.<Main>$(String[] args) in /workspace/tests/dotnet/prj/anon_queries/Program.cs:line 32
         at Program.<Main>$(String[] args) in /workspace/tests/dotnet/prj/anon_queries/Program.cs:line 34
         at Program.<Main>$(String[] args) in /workspace/tests/dotnet/prj/anon_queries/Program.cs:line 34
         at Program.<Main>(String[] args)