动态数据映射的存储过程

Question

我知道这一定已经解决了,但我很难找到解决方案.我已经尝试搜索:存储过程动态数据映射插入映射表在谷歌和这里.

我有一个DataMapping表

"OriginalColumn","OriginalTable","NewColumn","NewTable"

由于列名称建议此表将包含如何将一个表中的数据加载到另一个现有表中的元数据.

我想写一个会发出一个存储过程

select *  
from DataMapping 
where OriginalTable = XXXX 

然后利用这些信息就回来了动态创建和执行Insert into NewTable的基础OriginalColumn,以NewColumn映射.

---

以下是将生成示例问题的代码:

/****** Object:  Table [dbo].[DataMapping]    Script Date: 7/23/2018 11:34:11 AM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[DataMapping](
    [OriginalColumn] [sysname] NOT NULL,
    [OriginalTable] [sysname] NOT NULL,
    [NewColumn] [sysname] NOT NULL,
    [NewTable] [sysname] NOT NULL
) ON [PRIMARY]
GO
/****** Object:  Table [dbo].[destinationTable]    Script Date: 7/23/2018 11:34:12 AM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[destinationTable](
    [id] [int] NULL,
    [field1] [nvarchar](50) NULL,
    [field2] [nvarchar](50) NULL
) ON [PRIMARY]
GO
/****** Object:  Table [dbo].[TableA]    Script Date: 7/23/2018 11:34:12 AM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[TableA](
    [sourceID] [int] NULL,
    [sourceField1] [nchar](10) NULL,
    [sourceField2] [nvarchar](50) NULL
) ON [PRIMARY]
GO
/****** Object:  Table [dbo].[TableB]    Script Date: 7/23/2018 11:34:12 AM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[TableB](
    [sourceID] [int] NULL,
    [sourceField1] [nchar](10) NULL,
    [sourceField2] [nvarchar](50) NULL
) ON [PRIMARY]
GO
INSERT [dbo].[DataMapping] ([OriginalColumn], [OriginalTable], [NewColumn], [NewTable]) VALUES (N'sourceField1', N'TableA', N'field1', N'DestinationTable')
GO
INSERT [dbo].[DataMapping] ([OriginalColumn], [OriginalTable], [NewColumn], [NewTable]) VALUES (N'sourceField2', N'TableA', N'field2', N'DestinationTable')
GO
INSERT [dbo].[DataMapping] ([OriginalColumn], [OriginalTable], [NewColumn], [NewTable]) VALUES (N'sourceID', N'TableA', N'id', N'DestinationTable')
GO
INSERT [dbo].[DataMapping] ([OriginalColumn], [OriginalTable], [NewColumn], [NewTable]) VALUES (N'sourceField1', N'TableB', N'field1', N'DestinationTable')
GO
INSERT [dbo].[DataMapping] ([OriginalColumn], [OriginalTable], [NewColumn], [NewTable]) VALUES (N'sourceField2', N'TableB', N'field2', N'DestinationTable')
GO
INSERT [dbo].[DataMapping] ([OriginalColumn], [OriginalTable], [NewColumn], [NewTable]) VALUES (N'sourceID', N'TableB', N'id', N'DestinationTable')
GO
INSERT [dbo].[destinationTable] ([id], [field1], [field2]) VALUES (NULL, N'col1      ', NULL)
GO
INSERT [dbo].[destinationTable] ([id], [field1], [field2]) VALUES (NULL, N'col2      ', NULL)
GO
INSERT [dbo].[destinationTable] ([id], [field1], [field2]) VALUES (NULL, N'col1      ', N'12345ABC')
GO
INSERT [dbo].[destinationTable] ([id], [field1], [field2]) VALUES (NULL, N'col2      ', N'24681DEF')
GO
INSERT [dbo].[destinationTable] ([id], [field1], [field2]) VALUES (1, N'col1      ', N'12345ABC')
GO
INSERT [dbo].[destinationTable] ([id], [field1], [field2]) VALUES (2, N'col2      ', N'24681DEF')
GO
INSERT [dbo].[TableA] ([sourceID], [sourceField1], [sourceField2]) VALUES (1, N'col1      ', N'12345ABC')
GO
INSERT [dbo].[TableA] ([sourceID], [sourceField1], [sourceField2]) VALUES (2, N'col2      ', N'24681DEF')
GO
INSERT [dbo].[TableB] ([sourceID], [sourceField1], [sourceField2]) VALUES (2, N'B1234     ', N'9999')
GO
INSERT [dbo].[TableB] ([sourceID], [sourceField1], [sourceField2]) VALUES (2, N'B5678     ', N'9999')
GO

最终解决方案

这是最终解决方案,我在其中获得了下面的最佳答案,并将其转换为存储过程,允许我选择填充哪个目标表,以防您不想重新运行整个导入过程.

CREATE PROCEDURE [dbo].[DataMappingProc2]
(
@DestinationTable as VARCHAR(40)
)
AS 
    BEGIN
    DECLARE @Sql nvarchar(max) = ''

    SELECT @Sql += 'INSERT INTO '+ NewTable +'(' + 
            STUFF((SELECT ', ' + NewColumn
                   FROM dbo.DataMapping t1
                   WHERE t1.NewTable = t0.NewTable
                   AND t1.OriginalTable = t0.OriginalTable
                   And t1.NewTable = @DestinationTable
                   ORDER BY NewColumn
                   FOR XML PATH('')), 1, 2, '') +') ' + 
            'SELECT '+ 
            STUFF((SELECT ', ' + OriginalColumn
                   FROM dbo.DataMapping t2
                   WHERE t2.NewTable = t0.NewTable
                   AND t2.OriginalTable = t0.OriginalTable
                   And t2.NewTable = @DestinationTable
                   ORDER BY NewColumn
                   FOR XML PATH('')), 1, 2, '') +' FROM '+ OriginalTable +'; '
    FROM dbo.DataMapping t0
    WHERE t0.NewTable = @DestinationTable
    GROUP BY NewTable, OriginalTable

    EXEC (@Sql)

    Return 0
    END
GO

运行存储过程

DECLARE @return_value int
EXEC    @return_value = [dbo].[DataMappingProc2]
        @DestinationTable = N'DestinationTable'

SELECT  'Return Value' = @return_value
GO

Answer 1

更新：在编写我的原始答案时，我错误地假设每对表和列之间都会有一个唯一的映射（如果原始问题包含它现在包含的示例数据，则该假设将被避免） - 因此我的答案是错误的。

现在问题已更新以包含正确的示例数据，我可以更新我的答案 - 通过向子查询添加另一个条件并向原始查询添加一个分组，我已经设法获得了一个可行的解决方案：

DECLARE @Sql nvarchar(max) = ''

SELECT @Sql += 'INSERT INTO '+ NewTable +'(' + 
        STUFF((SELECT ', ' + NewColumn
               FROM dbo.DataMapping t1
               WHERE t1.NewTable = t0.NewTable
               AND t1.OriginalTable = t0.OriginalTable
               ORDER BY NewColumn
               FOR XML PATH('')), 1, 2, '') +') ' + 
        'SELECT '+ 
        STUFF((SELECT ', ' + OriginalColumn
               FROM dbo.DataMapping t2
               WHERE t2.NewTable = t0.NewTable
               AND t2.OriginalTable = t0.OriginalTable
               ORDER BY NewColumn
               FOR XML PATH('')), 1, 2, '') +' FROM '+ OriginalTable +'; '
FROM dbo.DataMapping t0  
GROUP BY NewTable, OriginalTable

更新了 rextster 链接

第一个版本

这是一种不需要使用光标的解决方案：

DECLARE @Sql nvarchar(max) = ''

SELECT @Sql += 'INSERT INTO '+ NewTable +'(' + 
        STUFF((SELECT ', ' + NewColumn
               FROM dbo.DataMapping t1
               WHERE t1.NewTable = t0.NewTable
               ORDER BY NewColumn
               FOR XML PATH('')), 1, 2, '') +') ' + 
        'SELECT '+ 
        STUFF((SELECT ', ' + OriginalColumn
               FROM dbo.DataMapping t2
               WHERE t2.NewTable = t0.NewTable
               ORDER BY NewColumn
               FOR XML PATH('')), 1, 2, '') +' FROM '+ OriginalTable +'; '
FROM dbo.DataMapping t0  

EXEC (@Sql)

借助 M.Ali 的示例数据， 您可以在 rextester 上看到现场演示。