Record Collection Count = 1, but Exists is return false?

Question

Hi All,
OracleDB: 10g
I have a collection record I am using to store information in a sproc. Before I do any work with it I check if any data exists in the record (l_tab_cost_rec.EXISTS(1)).
What is strange is l_tab_cost_rec.EXISTS(1) is returning false, but l_tab_cost_rec.Count is returning a count = 1?
Why is Exists returning false, but the count is returning 1?
Record Definition:
TYPE type_cost_rec IS RECORD
(item_id NUMBER
,item_cost NUMBER
,org_id NUMBER
TYPE tab_cost_rec IS TABLE OF type_cost_rec INDEX BY BINARY_INTEGER;
l_tab_cost_rec tab_cost_rec;

Answer 1

Becaues exists(1) checks if an element exists that has index 1:
SQL> declare
  2  type t is table of number index by binary_integer;
  3  v t;
  4  begin
  5   v(0):=0;
  6   dbms_output.put_line('count='||v.count);
  7   if v.exists(1) then
  8      dbms_output.put_line('1 exists!');
  9   else
10      dbms_output.put_line('1 doesn''t exist!');
11   end if;
12   if v.exists(0) then
13      dbms_output.put_line('0 exists!');
14   else
15      dbms_output.put_line('0 doesn''t exist!');
16   end if;
17  end;
18  /
count=1
1 doesn't exist!
0 exists!
PL/SQL procedure successfully completed.Max
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