Question

我正在撰写报告存储过程。我想获得非确认和非开票的采购订单的数量，能够（可选）过滤CustomerID。

我下面的内容按预期工作，但我担心a）它很慢而且b）CustomerID子句的WHERE部分有重复。

你会如何编写这个存储过程，Stack Overflow？

SELECT 
  (SELECT COUNT(*)
   FROM PurchaseOrder
   WHERE AcknowledgmentStatus <> 'Complete'
   AND (@CustID = 0 OR CustomerID = @CustID)
  ) AS NonAckd,
  (SELECT COUNT(*)
   FROM PurchaseOrder
   WHERE InvoiceStatus <> 'Complete'
   AND (@CustID = 0 OR CustomerID = @CustID)
  ) AS NonInvoiced

Answer 1

我不确定100％你追求的是什么，但你可以按照以下方式简化客户部分:(从[累]记忆中未经测试）

set @custID = nullif(@custID,0)

SELECT 
  (SELECT COUNT(*)
   FROM PurchaseOrder
   WHERE AcknowledgmentStatus <> 'Complete'
   AND ( CustomerID = isnull(@CustID,CustomerID) )
  ) AS NonAckd,
  (SELECT COUNT(*)
   FROM PurchaseOrder
   WHERE InvoiceStatus <> 'Complete'
   AND ( CustomerID = isnull(@CustID,CustomerID) )
  ) AS NonInvoiced

Answer 2

这样的事情：

SELECT Sum(Case When AcknowledgmentStatus <> 'Complete' Then 1 ELSE 0 END) as NonAckd
      ,Sum(Case When InvoiceStatus <> 'Complete'        Then 1 ELSE 0 END) as NonInvoiced 
  FROM PurchaseOrder 
 WHERE CustomerID = IsNull(NullIf(@CustID, 0), CustomerID)

Answer 3

你不能使用：

COUNT因为它会计算所有行（1或0不为空，因此它会计算它们）
COUNT DISTINCT将给出2（仅值1和0）

如果您删除状态检查，当然如果您可以处理零，它将运行得更快。

SELECT
    CASE WHEN AcknowledgmentStatus <> 'Complete' THEN 1 ELSE 0 END AS NonAckd,
    CASE WHEN InvoiceStatus <> 'Complete' THEN 1 ELSE 0 END AS NonInvoiced,
FROM
    PurchaseOrder
WHERE
    (AcknowledgmentStatus <> 'Complete' OR  InvoiceStatus <> 'Complete') --optional
    AND
    (@CustID = 0 OR CustomerID = @CustID)

报告存储过程 - 如何避免重复？

3 个答案: