Question

我有两个单独的表，每个表包含字符分隔的单元格。一个表包含所有关键数据，另一个表包含所有val数据。在应用程序中，两个表都被加载到记录集中，两个单元被分成两个数组，然后这些数组“并排”用于创建键/值对。

尝试将数据库与应用程序分离，我基本上会创建一个模拟此行为的视图。

我创建了一些示例表和数据来更好地说明它。

/* Create tables */
CREATE TABLE [dbo].[tblKeys](
    [KeyId] [int] NOT NULL, /*PK*/
    [KeyData] [nvarchar](max) NULL
)
CREATE TABLE [dbo].[tblValues](
    [ValId] [int] NOT NULL, /*PK*/
    [KeyId] [int] NOT NULL, /*FK*/
    [Language] [nvarchar](5) NOT NULL,
    [ValData] [nvarchar](max) NULL
)

/* Populate tables */
INSERT INTO [dbo].[tblKeys] ([KeyId], [KeyData]) VALUES
    (1, '1|2|3'),
    (2, '1|2|3|4'),
    (3, '2|1')
INSERT INTO [dbo].[tblValues] ([ValId], [KeyId], [Language], [ValData]) VALUES
    (1, 1, 'en',    'Apple|Orange|Pear'),
    (2, 1, 'sv-se', 'Äpple|Apelsin|Päron'),
    (3, 2, 'en',    'Milk|Butter|Cheese|Cream'),
    (4, 2, 'sv-se', 'Mjölk|Smör|Ost|Grädde'),
    (5, 3, 'en',    'Male|Female'),
    (6, 3, 'sv-se', 'Man|Kvinna')

视图中所需的最终结果如下所示：

| KeyId | KeyData | Language | ValData
+-------+---------+----------+----------+
|     1 |       1 |       en | Apple    |
|     1 |       2 |       en | Orange   |
|     1 |       3 |       en | Pear     |
|     1 |       1 |    sv-se | Äpple    |
|     1 |       2 |    sv-se | Apelsin  |
|     1 |       3 |    sv-se | Päron    |
...

等

我在StackOverflow上看到过类似的问题，但它们都以类似的方式处理单个表格。我需要倾斜两个表，同时使用两列KeyData和ValData中的数据位置作为siginficants重新组合成正确的键/值对。

我如何以有效的方式做到这一点？

[编辑]：数据库设计不是我的。这是我固有的一些旧废话。我知道这很糟糕。不如可怕的。

Answer 1

这对你有用。但是：你真的应该改变你的数据设计！

;WITH Splitted AS
(
    SELECT v.Language
          ,v.ValData
          ,v.ValId
          ,k.KeyData
          ,k.KeyId
          ,CAST('<x>' + REPLACE(v.ValData,'|','</x><x>') + '</x>' AS XML) AS ValData_XML 
          ,CAST('<x>' + REPLACE(k.KeyData,'|','</x><x>') + '</x>' AS XML) AS KeyData_XML 
    FROM tblValues AS v
    INNER JOIN tblKeys AS k ON v.KeyId=k.KeyId
)
,NumberedValData AS
(
    SELECT ROW_NUMBER() OVER(PARTITION BY KeyId,Language ORDER BY (SELECT NULL)) AS RowNumber
      ,KeyId
      ,Language
      ,A.B.value('.','varchar(max)') AS ValD 
    FROM Splitted
    CROSS APPLY Splitted.ValData_XML.nodes('/x') AS A(B)
)
,NumberedKeyData AS
(
    SELECT ROW_NUMBER() OVER(PARTITION BY KeyId,Language ORDER BY (SELECT NULL)) AS RowNumber
      ,KeyId
      ,Language
      ,A.B.value('.','varchar(max)') AS KeyD 
    FROM Splitted
    CROSS APPLY Splitted.KeyData_XML.nodes('/x') AS A(B)
)
,Combined AS
(
    SELECT nk.KeyId
          ,nk.KeyD
          ,nk.Language
          ,nv.ValD
    FROM NumberedKeyData AS nk
    INNER JOIN NumberedValData AS nv ON nk.KeyId=nv.KeyId AND nk.Language=nv.Language AND nk.RowNumber=nv.RowNumber
)
SELECT Combined.KeyId
      ,Combined.KeyD AS KeyData
      ,Splitted.Language  
      ,Combined.ValD AS ValData
FROM Splitted
INNER JOIN Combined ON Splitted.KeyId=Combined.KeyId AND Splitted.Language=Combined.Language
ORDER BY Splitted.KeyId,Splitted.

结果

KeyId   KeyData Language    ValData
   1    1       en          Apple
   1    2       en          Orange
   1    3       en          Pear
   1    1       sv-se       Äpple
   1    2       sv-se       Apelsin
   1    3       sv-se       Päron
   2    1       en          Milk
   2    2       en          Butter
 [...]

如何将两个单独表中的两列拆分为视图中连接的多行？

1 个答案: