Employee History Assignment Loading

Dear All,

I am working on employee assignments to upload their history data. Employee are exist and Ex-employee. I need a script to upload current and ex-employee history assignment.

I am using data track functionality in my script but it's only update one line of the 1st assignment not create or insert new lines.

Need to instert below lines into assignment table for ex-employee.

1.     01-jun-2000 to 28-jul-2004

2.     29-jul-2004 to 15-oct-2004

3.     16-oct-2004 to 08-sep-2013

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Current Dates are exists

1.     01-jun-2000 to 30-jun-2013

2.     01-jul-2013 to 6-sep-2013

3.     08-sep-2013 to 20-mar-2014.

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declare

  -- Local Variables

  lc_dt_ud_mode      VARCHAR2(100) := NULL;

  ln_assignment_id   NUMBER;