(_connection.QueryFirstOrDefault<decimal?>(" select `val` from dc_ana_deviation where sku=@sku and project=@project and field=@field and date_str=@date_str and field_type=@field_type ",new
(_connection.QueryFirstOrDefault<decimal?>(" select `val` from dc_ana_deviation where sku=@sku and project=@project and field=@field and date_str=@date_str and field_type=@field_type ",new