15
表who
MySQL的SELECT CASE WHEN東西然後返回空
wid--name-------father---mother
1----Daisy------David----Liza
2----Jenny------Joe------Judy
3----Meggy------Mike-----Manuela
4----Sarah------Joe------Judy
5----Chelsea----Bill-----Hillary
6----Cindy------David----Liza
7----Kelly------Joe------Judy
表ages
aid---whoid---age
1-----1--------0
2-----2--------0
3-----3-------14
4-----4-------30
5-----5-------22
6-----6-------17
7-----1-------18
我希望該列表的結果:
id---name------age
1----Meggy-----14
2----Cindy-----17
3----Daisy-----18 (Selected data that bigger than 0)
4----Chelsea---22
5----Sarah-----30
6----Jenny-----30 (Her age is 0 on ages table and Sarah's age with same father and mother)
7----Kelly-----30 (No data on ages table and Sarah's age with same father and mother)
我試過查詢:
SELECT
*,
(CASE age
WHEN '0' THEN (
SELECT age
FROM ages a
LEFT JOIN who w
ON w.wid = a.whoid
WHERE
w.father = father
AND
w.mother = mother
ORDER BY a.age DESC LIMIT 1
)
ELSE age
END
) AS newage
FROM who
LEFT JOIN ages
ON wid = whoid
ORDER BY newage
這是什麼問題?
謝謝。這解決了訂購問題,但仍然有選擇正確的年齡問題。 – baturalpdincdari 2011-01-11 15:48:27
@baturalpdincdari:別名表。 – Quassnoi 2011-01-11 15:49:52