mysql case when update code example

Example 1: update using case in mysql

UPDATE `table` SET `uid` = CASE
    WHEN id = 1 THEN 2952
    WHEN id = 2 THEN 4925
    WHEN id = 3 THEN 1592
    ELSE `uid`
    END
WHERE id  in (1,2,3)

Example 2: mysql case when on date

SELECT
  id,
  CASE
    WHEN date_activated > '2011-11-23 18:30:00' THEN 'after'
    WHEN date_activated > '2010-01-20 00:00:00' THEN 'before'
    ELSE 'not yet'
  END AS date_note
FROM table1;