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.
```
const Names & column_names,
    const StorageMetadataPtr & metadata_snapshot,
    SelectQueryInfo & query_info,
    ContextPtr local_context,
    QueryProcessingStage::Enum processed_stage,
    const size_t max_block_size,
    const unsigned num_streams)
{
    QueryPlan plan;
    read(plan, column_names, metadata_snapshot, query_info, local_context, processed_stage, max_block_size, num_streams);
    return plan.convertToPipe(
        QueryPlanOptimizationSettings::fromContext(local_context),
        BuildQueryPipelineSettings::fromContext(local_context));
}
void StorageDistributed::read(