Binder Error:
Contents of view were altered: types don't match! Expected [VARCHAR, VARCHAR, INTEGER], but found [VARCHAR, VARCHAR, "NULL"] instead

-- EXAMPLE 4 (pt1): Comment the following lines to see it work
-- If you don't create a view then there is no error
CREATE VIEW
  "tbl1" AS
  -- End of EXAMPLE 4 (pt1)
WITH
  data_infra as (
    select
      'a' as AMES,
      'b' as TONG
      -- Example 6: Unomment out the following line to see it work
      -- If there is more than one resulting row in the group by then there is not error
      -- union all
      -- select
      --   'c' as AMES,
      --   'b' as TONG
      --End Example 6
      -- Example 5: Comment out the following line to see it work
      -- If there is no group by then there is an error
    group by
      1
      -- End of Example 5
  )
SELECT
  -- Example 1: Comment the following lines to see it work
  -- If the CTE is used only once then there is no error
  case
    when 'b' in (
      select
        TONG
      from
        data_infra
    ) then 'tong'
    else 'Various'
  end as collapsed_TONG,
  --- End of Example 1
  -- Example 2: Comment the following lines to see it work
  -- If the CTE is used only once then there is no error
  case
    when 'ba' in (
      select
        TONG
      from
        data_infra
    ) then 'ames'
    else null
  end as collapsed_AMES,
  --- End of Example 2
  -- Example 3: Delete this line to see it work
  -- If there is no null column there is no error
  NULL AS NULL_COL;

-- Example 4 (pt2): Comment out the following line to see it work
SELECT
  *
FROM
  "tbl1";

-- End of EXAMPLE 4 (pt2)Exam