我可以使用子查詢連接字符串嗎？

Question

我甚至不知道如何正確地說出這個問題。我正在嘗試編寫一個查詢案例（狀態：關閉）的查詢，檢查特定用戶是否輸入了一個便箋，如果是，請檢查該便箋後面是否添加了便條（該便條會說明案件重新開放或不）。下面是我有：

SELECT DISTINCT scr.CaseId, scr.AssignedSRIdent, s.RepFullName FROM dbo.SupportCaseRoot scr 
INNER JOIN #comparison1 c ON c.CaseId = scr.CaseId 
INNER JOIN #comparison2 c2 ON c2.CaseId = scr.CaseId 
INNER JOIN dbo.servicereproot s ON s.SRIdent = scr.SRIdent 
INNER JOIN dbo.SupportCaseNote scn ON scn.CaseId = scr.CaseId 
WHERE scr.StatusId IN (4, 36, 37, 39, 28) 
AND c.DateCreated > c2.DateCreated 
AND scn.Description LIKE '%status%of%' + ' ' + (SELECT scs.Description FROM dbo.SupportCaseStatus scs WHERE scs.StatusId NOT IN (4, 36, 37, 39, 28)) 
ORDER BY scr.CaseId 

當我運行它，我得到這個錯誤：

Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression. 

我假設的最後一個AND語句和我在級聯愚蠢的嘗試，因爲。我希望它找到「[找到所有描述]的狀態」。任何人有任何建議？

Answer 1

你可以使用一些解決方案：

• 使用「頂部1」或「行偏移」久違的子查詢或單個值
  
• 使用聚合函數返回單一（爲前像Max。）在子查詢或值
  
• 與一個函數返回

Answer 2

這裏的誤差是在子表返回更個單值替換該子查詢一個值。

隔離子查詢並查看您獲得的結果。子查詢最多需要返回一個結果才能「可連接」。

Answer 3

嘗試在子查詢中相匹配，就像這樣：

SELECT DISTINCT scr.CaseId, scr.AssignedSRIdent, s.RepFullName 
FROM dbo.SupportCaseRoot scr 
INNER JOIN #comparison1 c ON c.CaseId = scr.CaseId 
INNER JOIN #comparison2 c2 ON c2.CaseId = scr.CaseId 
INNER JOIN dbo.servicereproot s ON s.SRIdent = scr.SRIdent 
INNER JOIN dbo.SupportCaseNote scn ON scn.CaseId = scr.CaseId 
WHERE scr.StatusId IN (4, 36, 37, 39, 28) 
AND c.DateCreated > c2.DateCreated 
AND EXISTS(
    SELECT 1 FROM dbo.SupportCaseStatus scs WHERE scs.StatusId NOT IN (4, 36, 37, 39, 28) 
    AND scn.Description LIKE ('%status%of%' + ' ' + scs.Description) 
) 
ORDER BY scr.CaseId