An instance of 'MySqlEFConfiguration' was set but this type was not discovered in the same assembly as the 'OracleDbContext' context. Either put the DbConfiguration type in the same assembly as the DbContext type, use DbConfigurationTypeAttribute on the DbContext type to specify the DbConfiguration type, or set the DbConfiguration type in the config file. See http://go.microsoft.com/fwlink/?LinkId=260883 for more information.
参考：https://stackoverflow.com/questions/26361592/same-application-different-databases-entity-framework-6-x-mysql-sql-server