Untitled

Is there a SQL Statement that allows me to copy and insert existing rows but with one column change?
Col1   Col2    Col3

  a       b       AA

  1       2       33

Col1   Col2    Col3

  a       b       **BB**

  1       2       **44**

INSERT INTO
  myTable (
    Col1,
    Col2,
    Col3
  )
SELECT
  Col1,
  Col2,               -- This is a specific example based on your comment.
  Col3 + 6            -- This just adds 6 to the existing value, but any SQL
FROM                  -- could actually go here, such as a CASE statement...
  myTable

CASE WHEN Col3 = 'AA' THEN '**BB**'
     WHEN Col3 = '33' THEN '**44**'
                      ELSE 'Unknown'
END,

INSERT INTO
  myTable (
    Col1,
    Col2,
    Col3
  )
SELECT
  OldTable.Col1,
  OldTable.Col2,
  COALESCE(NewTable.Col3, 'Unknown')
FROM
  myTable     AS OldTable
LEFT JOIN
  lookup      AS NewTable
    ON  OldTable.Col1 = NewTable.Col1
    AND OldTable.Col2 = NewTable.Col2

INSERT INTO table_name( col1, col2, col3 )
  SELECT col1,
         col2,
         (CASE WHEN col3 = 'AA'
                 THEN 'BB'
               WHEN col3 = '33'
                 THEN '44'
               ELSE null
            END)
    FROM table_name;