關於Oracle中多個條件的案例陳述

Question

CASE test
WHEN  NULL and  SUBSTR(('99999999' - Tst_Date),1,4) > 2009 THEN 'Medi'                     
WHEN   NULL and SUBSTR(('99999999' - Tst_Date),1,4) < 2009 THEN 'hills'
ELSE test
END AS "Phy"

我在上述案例陳述中遺漏了什么嗎？ 我一直在收到00905. 00000 - “缺少關鍵字”錯誤？

Answer 1

你的語法有點偏。 用這個：

CASE WHEN test IS NULL AND SUBSTR(('99999999' - Tst_Date),1,4) > 2009 THEN 'Medi'
     WHEN test IS NULL AND SUBSTR(('99999999' - Tst_Date),1,4) < 2009 THEN 'hills'
     ELSE test
END AS "Phy"