sql - 多次使用一个 CTE

Question

我有这个，但在设置总数时出现错误。 为什么我无法多次访问 cte？

ALTER PROCEDURE [dbo].[GetLeaguePlayers]
(
    @idleague int,
    @pageNumber int,
    @pageSize int,
    @total int OUTPUT
)
AS
WITH CTEPlayers AS
(
    SELECT ROW_NUMBER() OVER (ORDER BY p.Name) AS RowNumber, p.Id, p.Name, t.Name AS Team
    FROM Players p INNER JOIN Teams t ON p.IdTeam=t.Id INNER JOIN Leagues l ON l.Id=t.IdLeague
    WHERE l.Id=@idleague
)
SELECT Id, Name
FROM CTEPlayers c
WHERE RowNumber>@pageSize*(@pageNumber-1) AND RowNumber<@pageSize*@pageNumber;
SET @total = ( SELECT COUNT(*) FROM CTEPlayers )

Answer 1

CTE 基本上是一次性 View 。它仅持续一条语句，然后自动消失。

您的选择包括:

• 再次重新定义CTE。这就像从 WITH... 复制粘贴到定义末尾到 SET 之前一样简单。

• 将结果放入 #temp 表或 @table 变量

• 将结果具体化为真实表格并引用

• 稍微更改为仅从 CTE 中选择 SELECT COUNT:

.

SELECT @total = COUNT(*)
FROM Players p 
INNER JOIN Teams t 
    ON p.IdTeam=t.Id 
INNER JOIN Leagues l 
    ON l.Id=t.IdLeague
WHERE l.Id=@idleague