text: ALTER TABLE
    sims.program_years
  ADD
    COLUMN IF NOT EXISTS program_year_prefix VARCHAR(4) NOT NULL DEFAULT '';
  
  COMMENT ON COLUMN sims.program_years.program_year_prefix IS 'Program Year prefix for a particular Program year.';
  
  UPDATE
    sims.program_years
  SET
    program_year_prefix = '2021'
  WHERE
    program_year = '2021-2022';
  
  UPDATE
    sims.program_years
  SET
    program_year_prefix = '2022'
  WHERE
    program_year = '2022-2023';
  
  UPDATE
    sims.program_years
  SET
    program_year_prefix = '2023'
  WHERE
    program_year = '2023-2024';
  
  -- Removing the dummy constraint created just to allow us
  -- to add a "NOT NULL" column in an exising table.
  
  ALTER TABLE
    sims.program_years
  ALTER COLUMN
    program_year_prefix DROP DEFAULT;