Question

我想在行存在注释时获取增量索引。我试图用ROW_Number（）实现相同，但似乎用于生成它的方法存在问题。

SELECT *                    RowNo,
       (SELECT CASE
                 WHEN LEN(Value) > 0 THEN ROW_NUMBER()
                                            OVER (
                                              ORDER BY ID)
                 ELSE ''
               END
        FROM   Dictionary
        WHERE  ID = ABC.ID) Note
FROM   ABCD AS ABC WITH(NOLOCK)
       INNER JOIN XYZ AS XYZ WITH(NOLOCK)
               ON ABC.Id = XYZ.ID
WHERE  ABC.Id = 10

预期输出：

    ID Name Note
    1  A    1
    2  B    
    3  C    2
    4  D    
    5  E    
    6  F    3

Answer 1

此处不需要子查询，并且您希望使用partition by参数将values与len(value)>0的{{1}}与没有值的SELECT ID, Name, CASE WHEN LEN(Value)>0 THEN ROW_NUMBER() OVER ( PARTITION BY CASE WHEN LEN(Value)>0 THEN 1 ELSE 0 END ORDER BY ID) ELSE '' END as Note FROM ABCD AS ABC WITH(NOLOCK) INNER JOIN XYZ AS XYZ WITH(NOLOCK) ON ABC.Id = XYZ.ID Where ABC.Id = 10分开：

{{1}}

Answer 2

我想也许您需要更改方法以使Dictionary查询成为“主要”查询。如果不确切知道你的桌子是什么样的话，很难说。您的预期输出中的“Id”来自哪个表？

试试这样：

WITH cte AS (
  SELECT ID, ROW_NUMBER() OVER (ORDER BY ID) AS Note
  FROM Dictionary WHERE ID=10
  AND LEN(Value)>0
)
SELECT ABC.ID, [Name], cte.Note
FROM  ABCD AS ABC WITH(NOLOCK) 
INNER JOIN XYZ AS XYZ WITH(NOLOCK) ON ABC.Id = XYZ.ID
LEFT OUTER JOIN cte ON ABC.Id=cte.ID

获取特定行的增量索引

2 个答案: