You can use CREATE TABLE AS with a SELECT subquery to copy data from a foreign table into a permanent table without a primary index. See Example: Copying Data from Foreign Table into Permanent Table.
Internally, the SELECT subquery performs an INSERT ... SELECT operation with the HASH BY RANDOM clause to provide even distribution of data. The HASH BY RANDOM clause is the default for an INSERT … SELECT operation from a foreign table into a permanent table without a primary index. You can disable this behavior.
This statement disables the random distribution of rows for the session.
SET QUERY_BAND = 'DisableHashByRandom = ON' FOR SESSION;
This statement disables the random distribution of rows for the transaction.
SET QUERY_BAND = 'DisableHashByRandom = ON' FOR TRANSACTION;