Postgres Citus error "complex joins are only supported when all distributed tables are joined on their distribution columns with equal operator"

Question

I have two tables defined as distributed in Citus based on the same field:

select create_distributed_table('gedi','clould_metadata_id');
select create_distributed_table('cloud_metadata','clould_metadata_id');

The clould_metadata_id is unique in cloud_metadata, gedi table stores millions of records, cloud_metadata stores around 3000.

When I try to inner join those tables using:

select * from cloud_metadata cm 
inner join gedi g 
on cm.clould_metadata_id = g.clould_metadata_id 

I get the error message "SQL Error [0A000]: ERROR: complex joins are only supported when all distributed tables are joined on their distribution columns with equal operator".

I believe that's precisely what I'm trying to do, join those tables using de distribution columns, so what I'm doing wrong?

Answer 1

Is possible you use 'create_reference_table()'. On this way is possible using join clausule. But this way working only if you don't need use 'create_distributed_table()'