SQL查詢選擇計數= 0

Question

好的，我需要一個T-SQL這個專家。

我有一個名爲PackageStoreEvents的表，它有一個packageid，storecode和一個eventcode字段。我想返回storecode 2406的packageid值，其中eventcode = 6的計數爲0.

我該怎麼做？

我被困在這一個。

感謝您的幫助

Answer 1

這不是非常漂亮，但應該工作。您在連接條件中將連接留在同一個表中，包括事件代碼，聲明右表沒有包含IS NULL的行，然後執行DISTINCT以避免將以其他方式返回的許多行。

SELECT DISTINCT p1.packageid 
FROM PackageStoreEvents p1 
     LEFT JOIN 
       PackageStoreEvents p2 
       ON p1.packageid = p2.packageid 
       AND p1.storecode = p2.storecode 
       AND p2.eventcode = 6 
WHERE p2.packageid IS NULL 
AND p1.storecode = 2406 

Answer 2

也許這?:

SELECT PackageID 
FROM PackageStoreEvents 
WHERE Storecode = 2406 and EventCode = 6 
GROUP BY PackageID 
HAVING COUNT(EventCode) = 0 

Answer 3

SELECT packageid 
FROM 
PackageStoreEvents p1 
WHERE storecode = 2406 
AND NOT EXISTS (SELECT * FROM PackageStoreEvents p2 
       WHERE p1.packageid = p2.packageid 
       AND p1.storecode = p2.storecode 
       AND p2.eventcode = 6) 

Answer 4

假設我正確地理解這個問題，我會用的東西沿着這行：

-- PackageStoreEvents (packageid, storecode, eventcode) 

SELECT DISTINCT packageid 
    FROM PackageStoreEvents r 
WHERE storecode = 2406 
    AND NOT EXISTS (SELECT * 
         FROM PackageStoreEvents cnt 
        WHERE cnt.packageid = r.packageid 
         AND cnt.storecode = r.storecode 
         AND cnt.eventcode = 6) 

Answer 5

嘗試：

select packageid 
from PackageStoreEvents 
where storecode = 2406 
group by packageid 
having sum(case eventcode when 6 then 1 else 0 end)=0; 

用於單遍查詢。