这只会返回带有注释的案例：

SELECT c.*,
       x.*
  FROM CASES c
  JOIN NOTES x ON x.case_id = c.case_id
  JOIN (SELECT n.case_id,
               MAX(n.note_date) AS max_note_date
          FROM NOTES n
      GROUP BY n.case_id) y ON y.case_id = x.case_id
                           AND y.max_note_date = x.note_date

如果需要所有案例，无论是否附带注释：

   SELECT c.*,
          x.*
     FROM CASES c
LEFT JOIN NOTES x ON x.case_id = c.case_id
     JOIN (SELECT n.case_id,
                  MAX(n.note_date) AS max_note_date
             FROM NOTES n
         GROUP BY n.case_id) y ON y.case_id = x.case_id
                              AND y.max_note_date = x.note_date