How can output result of multi select in Function of Postgresql? -

i have function as:

create or replace function f_compare_data_extract(tm_id_1 integer,tm_subid_1 integer,tm_id_2 integer,tm_subid_2 integer ) returns integer $$   begin --select * a; --select * b; --select * c;  return 0; end $$ language 'plpgsql' ; 

i want output result of 3 query when run function : select f_compare_data_extract(13,2967,13,2968);

 select * a;  select * b;  select * c; 

postgresql doesn't support returning multiple result sets single command.

if selects a, b , c return data in same format, can union them together, return them 1 result set.

if return data in different formats, can still union them together, you'll need add lots of nulls.

alternatively, have function create , populate temporary tables. execute function , select temp tables in separate commands.

as final option, return data encoded somehow, e.g. using row_to_json