freeload=> select 935::bigint in (select fn_descendents('trip'::varchar,61::bigint)); ERROR: operator does not exist: bigint = bigint[] LINE 1: select 935::bigint in (select fn_descendents('trip'::varchar... ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.
This is probably super obvious but I'm not getting it right now.