create OR REPLACE FUNCTION test()
RETURNS int4 AS
$BODY$
declare
r RECORD;
num int4 := 0;
sql "varchar" := 'select f_data_type from t_water_arguments group by f_data_type having count(*) >= 2 limit 1';
begin
FOR r IN EXECUTE sql LOOP
num = r.f_data_type;
end LOOP;
return num;
end
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
select test();
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