java - PostgreSQL: An error occured in SQL statement: ERROR: syntax error at or near "RETURNING" -

i've created stored procedure works when using command line , db manager (dbeaver).

create or replace function scores(int, int, int) returns void $$  begin     if exists (select * tab_scores pk_id = $1)         update tab_scores set         score = score + $2,         most_recent_level = $3         pk_id = $1;     else         insert tab_scores(int, int, int) values ($1, $2, $3);     end if; end; $$ language plpgsql; 

when attempt call procedure through java following error:

an error occured in sql statement: error: syntax error @ or near "returning" position: 38

i've looked around , can't find solution this. using postgresql-9.2 jdbc