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。我尝试搜索：存储过程动态数据映射插入映射 table 在 Google 和此处。

我有一个数据映射 table 说

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

正如列名所示，此 table 将包含有关如何将一个 table 中的数据加载到另一个现有 table 中的元数据。

我想编写一个存储过程来发出一个

select *  
from DataMapping 
where OriginalTable = XXXX

然后使用返回的信息根据 OriginalColumn 到 NewColumn 的映射动态创建和执行 Insert into NewTable。

下面是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

这是最终的解决方案，我采用了下面的最佳答案并将其转换为一个存储过程，允许我们选择我填充的目标 table，以防您不希望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

示例数据

CREATE TABLE dbo.DataMapping (   OriginalColumn     SYSNAME
                                ,OriginalTable      SYSNAME
                                ,NewColumn          SYSNAME
                                ,NewTable           SYSNAME)

INSERT INTO dbo.DataMapping
(   OriginalColumn
  , OriginalTable
  , NewColumn
  , NewTable)
VALUES 
    (   'Col1' , 'TableA' , 'Col_1' , 'TableAN') ,  (   'Col2' , 'TableA' , 'Col_2' , 'TableAN') 
  , (   'Col3' , 'TableA' , 'Col_3' , 'TableAN') ,  (   'Col1' , 'TableB' , 'Col_1' , 'TableBN') 
  , (   'Col2' , 'TableB' , 'Col_2' , 'TableBN') , (   'Col3' , 'TableB' , 'Col_3' , 'TableBN');

查询

Declare   @O_Cols           sysname
        , @N_Cols           sysname
        , @O_Tabl           sysname
        , @N_Tabl           sysname
        , @InsertColsList   NVARCHAR(MAX) =''
        , @SelectColsLIst   NVARCHAR(MAX) =''
        , @Sql              NVARCHAR(MAX);

DECLARE Cur CURSOR LOCAL FAST_FORWARD FOR
SELECT OriginalColumn , NewColumn
FROM dbo.DataMapping
WHERE OriginalTable = 'TableA'


OPEN Cur

 FETCH NEXT FROM Cur INTO @O_Cols , @N_Cols

WHILE (@@FETCH_STATUS = 0)
BEGIN
        SET @SelectColsLIst += ISNULL(',' + QUOTENAME(@O_Cols), '');
        SET @InsertColsList += ISNULL(',' + QUOTENAME(@N_Cols), '');

    FETCH NEXT FROM Cur INTO @O_Cols , @N_Cols
END

CLOSE Cur
DEALLOCATE Cur;

    SET @SelectColsLIst = STUFF(@SelectColsLIst, 1 ,1,'');
    SET @InsertColsList = STUFF(@InsertColsList, 1 ,1,'');


SELECT TOP 1  @O_Tabl = OriginalTable ,  @N_Tabl = NewTable 
FROM dbo.DataMapping
WHERE OriginalTable = 'TableA'

 SET @Sql = N' INSERT INTO ' + @N_Tabl + N'( ' + @InsertColsList + N' )'
          + N' SELECT ' + @SelectColsLIst
          + N' FROM ' + @O_Tabl;


PRINT @Sql 
--EXEC sp_executesql @Sql;

备注

我假设数据仅来自一个 table 并且仅流向一个 table，列名在源和目标 table 中可以不同并且table 名称可以不同，但始终是一对一的映射。

Answer 2

更新： 在写我原来的答案时，我错误地认为每对表和列之间会有一个唯一的映射（如果原来的问题包括它现在包含的示例数据该假设将被避免）-因此我的回答是错误的。

现在问题已更新为包含适当的示例数据，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分组依据，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

Updated rextster link

第一个版本

这是一种不需要使用游标的解决方案：

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)

感谢 M.Ali 的示例数据，您可以看到 live demo on rextester。

Answer 3

最后我选择了Zohar的方案；但是我确实很喜欢 M Ali 的解决方案。下面是我如何将 M Ali 的解决方案修改为存储过程，以便我可以针对不同的源表多次调用它。

Zohar 的解决方案也可以调整为仅处理特定的表，但就目前而言，它很好。

CREATE PROCEDURE [dbo].[DataMappingProc]
(
@Tblname as VARCHAR(10)
)
AS 
    BEGIN

    Declare   @O_Cols           sysname
            , @N_Cols           sysname
            , @O_Tabl           sysname
            , @N_Tabl           sysname
            , @InsertColsList   NVARCHAR(MAX) =''
            , @SelectColsLIst   NVARCHAR(MAX) =''
            , @Sql              NVARCHAR(MAX);


    DECLARE Cur CURSOR LOCAL FAST_FORWARD FOR
    SELECT OriginalColumn , NewColumn
    FROM dbo.DataMapping
    WHERE OriginalTable = @Tblname

    OPEN Cur

     FETCH NEXT FROM Cur INTO @O_Cols , @N_Cols

    WHILE (@@FETCH_STATUS = 0)
    BEGIN
            SET @SelectColsLIst += ISNULL(',' + QUOTENAME(@O_Cols), '');
            SET @InsertColsList += ISNULL(',' + QUOTENAME(@N_Cols), '');

        FETCH NEXT FROM Cur INTO @O_Cols , @N_Cols
    END

    CLOSE Cur
    DEALLOCATE Cur;

        SET @SelectColsLIst = STUFF(@SelectColsLIst, 1 ,1,'');
        SET @InsertColsList = STUFF(@InsertColsList, 1 ,1,'');


    SELECT TOP 1  @O_Tabl = OriginalTable ,  @N_Tabl = NewTable 
    FROM dbo.DataMapping
    WHERE OriginalTable = 'TableA'

     SET @Sql = N' INSERT INTO ' + @N_Tabl + N'( ' + @InsertColsList + N' )'
              + N' SELECT ' + @SelectColsLIst
              + N' FROM ' + @O_Tabl;


    EXEC sp_executesql @Sql;
    RETURN 0
    END;
GO

动态数据映射的存储过程

Stored Procedure for dynamic data mapping

sql

sql-server

stored-procedures

data-mapping