postgres dynamic sql

dynamic.sql

drop function if exists exec(text, text[]);
create function exec(sql text, params text[] default '{}') returns void
language 'plpgsql' as $$
begin 
    execute format(sql, variadic params); 
end 
$$;
-- select exec('select 1');

drop function if exists query(text, text[]);
create function query(sql text, params text[] default '{}') returns setof record
language 'plpgsql' as $$
begin 
    return query execute format(sql, variadic params); 
end 
$$;
-- select * from generate_series(1, 10) i, query('select generate_series(%s, %s::int + 10)', array[i::text, i::text]) as g(ii int);