The only way to use this feature is to specify an empty database name in Distributed table definition, but then you get a warning:

```
CREATE TABLE `demo_loan_all` (...) ENGINE=Distributed(test_cluster_two_shards_different_databases, '', demo_loan_01568, cityHash64(id));

<Warning> StorageDistributed (demo_loan_all): Name of remote database is empty. Default database will be used implicitly.
```
#include <Storages/StorageDistributed.h>
#include <Databases/IDatabase.h>
#include <Disks/IDisk.h>
#include <DataStreams/RemoteBlockInputStream.h>
#include <DataTypes/DataTypeFactory.h>
#include <DataTypes/DataTypeUUID.h>
#include <DataTypes/DataTypesNumber.h>
#include <Storages/Distributed/DistributedBlockOutputStream.h>
#include <Storages/StorageFactory.h>
#include <Storages/AlterCommands.h>
#include <Columns/ColumnConst.h>