ORA-04031: unable to allocate 4708660 bytes of shared memory

I am running Oracle 11g R1 on my local development machine.

I have been trying to run an anonymous block to test the FORALL statement in Oracle to insert 25,000 records.

I get the following error:

ORA-04031: unable to allocate 4708660 bytes of shared memory ("shared pool","DECLARE
  -- temp_rec temp%R...","PL/SQL SOURCE","PLD: Source Heap")
04031. 00000 -  "unable to allocate %s bytes of shared memory ("%s","%s","%s","%s")"
*Cause:    More shared memory is needed than was allocated in the shared
           pool.
*Action:   If the shared pool is out of memory, either use the
           dbms_shared_pool package to pin large packages,
           reduce your use of shared memory, or increase the amount of
           available shared memory by increasing the value of the
           INIT.ORA parameters "shared_pool_reserved_size" and
           "shared_pool_size".
           If the large pool is out of memory, increase the INIT.ORA
           parameter "large_pool_size".

I tried looking here and here but wasn’t able to resolve this issue.

I have tried the following:

ALTER SYSTEM FLUSH BUFFER_CACHE;  
ALTER SYSTEM FLUSH SHARED_POOL;
ALTER SYSTEM SET cursor_sharing = 'SIMILAR' SCOPE=BOTH;

Please help.

EDIT

The code I am using is as follows:

DECLARE
  TYPE t_varchar IS TABLE OF varchar(512 char);
  biz_hierarchy t_varchar := t_varchar();
  project_team t_varchar := t_varchar();
  user_roles t_varchar := t_varchar();
  username t_varchar := t_varchar();
  sso t_varchar := t_varchar();
BEGIN
  SELECT *
  BULK COLLECT INTO biz_hierarchy, project_team, user_roles, username, sso
  FROM ... -- Query fetches 25000 records

  FORALL i IN biz_hierarchy.FIRST..biz_hierarchy.LAST
    INSERT INTO temp VALUES (biz_hierarchy(i), project_team(i),
                              user_roles(i), username(i), sso(i));

END;
/

The error returned by Oracle does not mention the line number. If I try loading 5000 records, the code block runs successfully. Fails when I try with 25000.