選擇案例Statment單行子查詢返回不止一行

Question

需要從那時到價值只返回，但我的查詢返回的1S

SELECT 
CASE WHEN S.ITEM_ID<>0 THEN 1 
END AS "UomLevelEditable" 
FROM BIZZXE_V2_SCH.PO_REQUEST_ITEMS S WHERE S.ITEM_Id =209 AND S.UOM_ID= 55 

Answer 1

如果你想正是一排，然後用聚合：

SELECT MAX(CASE WHEN S.ITEM_ID <> 0 THEN 1 END) AS "UomLevelEditable" 
FROM BIZZXE_V2_SCH.PO_REQUEST_ITEMS S 
WHERE S.ITEM_Id = 209 AND S.UOM_ID = 55; 

如果你想最多一排，然後用rownum = 1：

SELECT (CASE WHEN S.ITEM_ID <> 0 THEN 1 END) AS "UomLevelEditable" 
FROM BIZZXE_V2_SCH.PO_REQUEST_ITEMS S 
WHERE S.ITEM_Id = 209 AND S.UOM_ID = 55 AND rownum = 1; 

Answer 2

我認爲這可能對您有所幫助，我在下面用鮮明。

SELECT 
DISTINCT CASE WHEN S.ITEM_ID<>0 THEN 1 
END AS "UomLevelEditable" 
FROM BIZZXE_V2_SCH.PO_REQUEST_ITEMS S WHERE S.ITEM_Id =209 AND S.UOM_ID= 55