Question

我有以下选择声明......

SELECT ROW_NUMBER() OVER(order by cola) as [id], cola
  FROM Table1

这构成了我想要作为@var插入的所有值的表格，现在它可以工作但我必须每次都指定@var ...

 SELECT @var AS [Cola], (

            SELECT COUNT(*)
              FROM vwTableA AS Z
             WHERE Cola = COALESCE(@var,Cola)
               AND NOT EXISTS (

                        SELECT * 
                          FROM TableB
                         WHERE Colb = Z.Colb

                              )

  ) AS [NewCol1],
  (

            SELECT COUNT(*)
              FROM vwTableB AS Y
             INNER JOIN TableC AS C
                ON Y.Colc = C.Colc
             WHERE Y.Cola = @var

  ) AS [NewCol2],
  (

            SELECT COUNT(*)
              FROM vwTableC AS X
             INNER JOIN TableD AS D
                ON X.Colc = D.Colc
             WHERE X.Cola = @var

  ) AS [NewCol3]

所以我想要通过我显示的第一个Select / Table中的“cola”的所有值来运行第二次选择，而不是必须指定@var并且每次只返回一行。我怎样才能做到这一点？

Answer 1

如果您使用Common Table Expression CTE，您可以使用它来加入您的其他声明

with var as 
( SELECT ROW_NUMBER() OVER(order by cola) as [id], cola
  FROM Table1)


SELECT var.id  AS [Cola], (

            SELECT COUNT(*)
              FROM vwTableA AS Z
             WHERE Cola = COALESCE(var.id,Cola)
               AND NOT EXISTS (

                        SELECT * 
                          FROM TableB
                         WHERE Colb = Z.Colb

                              )

  ) AS [NewCol1],
  (

            SELECT COUNT(*)
              FROM vwTableB AS Y
             INNER JOIN TableC AS C
                ON Y.Colc = C.Colc
             WHERE Y.Cola = var.id

  ) AS [NewCol2],
  (

            SELECT COUNT(*)
              FROM vwTableC AS X
             INNER JOIN TableD AS D
                ON X.Colc = D.Colc
             WHERE X.Cola = var.id

  ) AS [NewCol3]
FROM var

使用Table2条件中的Table1列值将Table1与Table2连接

1 个答案: