plpgsql function no results - arrays

Question

I have done the following function in plpgsql. It works fine and the it returns 'OK', BUT for some reason it inputs nothing in the table temp.
CREATE OR REPLACE FUNCTION public.get_route(node integer[])
RETURNS character varying AS
$BODY$DECLARE
i int := 0;
_r record;
vertex int;
BEGIN
FOREACH i IN ARRAY node
LOOP
IF( i < (array_length(node, 1) - 1))
THEN
FOR _r IN EXECUTE 'select * from shortest_path(''
select id as id, source_id::int4 as source, target_id::int4 as target, cost, reverse_cost
from network_of_point'','|| node[i] ||','|| node[i+1] ||', true, true)'
LOOP
vertex := _r.vertex_id;
EXECUTE 'insert into temp
select nextval(''road_intersection_id_seq''), point
from distinct_network_point
where distinct_network_point.id ='|| vertex;
END LOOP;
i = i + 1;
END IF;
END LOOP;
RETURN 'OK';
END;$BODY$
The following is the synatx I am using to call the function:
select get_route('{2,7}')

Answer 1

It doesn't work because this line
IF( i < (array_length(node, 1) - 1))
You're testing if 2 or 7 (taken from your example) are less than the length of the array, that's valued 2.
That's because your next queries are never executed.

Answer 2

Because of this line, inner part of code never executed.
IF( i < (array_length(node, 1) - 1))
Actually you are extracting value of i from node array
FOREACH i IN ARRAY node
which has value 2 or 7 as in your example and you are treating i as node index which is wrong. I have created a separate int variable value, now we can use i as array index.
I think you want to achieve this.
CREATE OR REPLACE FUNCTION public.get_route(node integer[])
RETURNS character varying AS
$BODY$
DECLARE
i int := 1;
_r record;
vertex int;
value int;
BEGIN
FOREACH value IN ARRAY node
LOOP
IF( i < (array_length(node, 1)))
THEN
FOR _r IN EXECUTE 'select * from shortest_path(''
select id as id, source_id::int4 as source, target_id::int4 as target, cost, reverse_cost
from network_of_point'','|| node[i] ||','|| node[i+1] ||', true, true)'
LOOP
vertex := _r.vertex_id;
EXECUTE 'insert into temp
select nextval(''road_intersection_id_seq''), point
from distinct_network_point
where distinct_network_point.id ='|| vertex;
END LOOP;
i = i + 1;
END IF;
END LOOP;
RETURN 'OK';
END;
$BODY$ language plpgsql;