Orders (OrderID, OrderStatus, OrderNumber)
OrderItems(OrderItemID, OrderID, ItemID, OrderItemStatus)
訂單:2537個記錄 訂單項目:1319個記錄
我已經創建了
-
指標
- Orders(OrderStatus)
- OrderItems(OrderID)
- 的OrderItems(OrderItemStatus)
我有以下SQL語句(由LinqToSql產生的),在執行時,有: - 持續時間= 8789 - 讀= 7809.
exec sp_executesql N'SELECT COUNT(*) AS [value]
FROM [dbo].[Orders] AS [t0]
WHERE ([t0].[OrderStatus] = @p0) OR (EXISTS(
SELECT NULL AS [EMPTY]
FROM [dbo].[OrderItems] AS [t1]
WHERE ([t1].[OrderID] = [t0].[OrderID]) AND ([t1].[OrderItemStatus] = @p1)
))',N'@p0 nvarchar(2),@p1 nvarchar(2)',@p0=N'KE',@p1=N'KE'
是否還有其他哪些我可以做得更快嗎?
你能證明爲什麼會這樣嗎? http://stackoverflow.com/questions/1221559/count-vs-count1/1221649#1221649 – gbn 2010-09-17 17:09:07