我正在寻找一种有效的方法将行转换为SQL服务器中的列，我听说PIVOT不是很快，我需要处理大量的记录。这是我的例子： ------------------------------- | Id | Value | ColumnName | ------------------------------- | 1 | John | FirstName | | 2 | 2.4 | Amount | | 3 | ZH1E4A | PostalCode | | 4 | Fork | LastName | | 5 | 857685 | AccountNumber | -------------------------------这是我的结果：---------------------------------------------------------------------| FirstName |Amount| PostalCode | LastName | AccountNumber |---------------------------------------------------------------------| John | 2.4 | ZH1E4A | Fork | 857685 |---------------------------------------------------------------------我该如何建立结果？
2 回答
拉丁的传说
TA贡献1789条经验 获得超8个赞
有几种方法可以将多行中的数据转换为列。在SQL Server中，您可以使用该PIVOT函数将数据从行转换为列：
select Firstname, Amount, PostalCode, LastName, AccountNumberfrom( select value, columnname from yourtable) dpivot( max(value) for columnname in (Firstname, Amount, PostalCode, LastName, AccountNumber)) piv;
见演示。
如果您columnnames想要转置的数量未知，则可以使用动态SQL：
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)select @cols = STUFF((SELECT ',' + QUOTENAME(ColumnName)
from yourtable group by ColumnName, id o
rder by id FOR XML PATH(''), TYPE ).value('.', 'NVARCHAR(MAX)')
,1,1,'')set @query = N'SELECT ' + @cols + N' from
(
select value, ColumnName
from yourtable
) x
pivot
(
max(value)
for ColumnName in (' + @cols + N')
) p 'exec sp_executesql @query;见演示。
如果您不想使用该PIVOT函数，则可以将聚合函数与CASE表达式一起使用：
select max(case when columnname = 'FirstName' then value end) Firstname, max(case when columnname = 'Amount' then value end) Amount, max(case when columnname = 'PostalCode' then value end) PostalCode, max(case when columnname = 'LastName' then value end) LastName, max(case when columnname = 'AccountNumber' then value end) AccountNumberfrom yourtable
见演示。
这也可以使用多个连接来完成，但是您需要一些列来关联样本数据中没有的每一行。但基本语法是：
select fn.value as FirstName, a.value as Amount, pc.value as PostalCode, ln.value as LastName, an.value as AccountNumberfrom yourtable fnleft join yourtable a on fn.somecol = a.somecol and a.columnname = 'Amount'left join yourtable pc on fn.somecol = pc.somecol and pc.columnname = 'PostalCode'left join yourtable ln on fn.somecol = ln.somecol and ln.columnname = 'LastName'left join yourtable an on fn.somecol = an.somecol and an.columnname = 'AccountNumber'where fn.columnname = 'Firstname'
神不在的星期二
TA贡献1963条经验 获得超6个赞
由于旋转数据仍然很热，我决定从中添加一些东西。这不仅仅是一个单一的脚本，而是为您提供了更多的可能性。首先需要部署3个脚本：1）用户定义的TABLE类型[ ColumnActionList] - >保存数据作为参数2）SP [ proc_PivotPrepare] - >准备我们的数据3）SP [ proc_PivotExecute] - >执行脚本
CREATE TYPE [dbo].[ColumnActionList] AS TABLE(
[ID] [smallint] NOT NULL,
[ColumnName] [nvarchar](128) NOT NULL,
[Action] [nchar](1) NOT NULL
);
GO
CREATE PROCEDURE [dbo].[proc_PivotPrepare]
(
@DB_Name nvarchar(128),
@TableName nvarchar(128)
)
AS
----------------------------------------------------------------------------------------------------
-----| Author: Bartosz
----------------------------------------------------------------------------------------------------
SELECT @DB_Name = ISNULL(@DB_Name,db_name())
DECLARE @SQL_Code nvarchar(max)
DECLARE @MyTab TABLE (ID smallint identity(1,1), [Column_Name] nvarchar(128), [Type] nchar(1), [Set Action SQL] nvarchar(max));
SELECT @SQL_Code = 'SELECT [<| SQL_Code |>] = '' '' '
+ 'UNION ALL '
+ 'SELECT ''----------------------------------------------------------------------------------------------------'' '
+ 'UNION ALL '
+ 'SELECT ''-----| Declare user defined type [ID] / [ColumnName] / [PivotAction] '' '
+ 'UNION ALL '
+ 'SELECT ''----------------------------------------------------------------------------------------------------'' '
+ 'UNION ALL '
+ 'SELECT ''DECLARE @ColumnListWithActions ColumnActionList;'''
+ 'UNION ALL '
+ 'SELECT ''----------------------------------------------------------------------------------------------------'' '
+ 'UNION ALL '
+ 'SELECT ''-----| Set [PivotAction] (''''S'''' as default) to select dimentions and values '' '
+ 'UNION ALL '
+ 'SELECT ''-----|'''
+ 'UNION ALL '
+ 'SELECT ''-----| ''''S'''' = Stable column || ''''D'''' = Dimention column || ''''V'''' = Value column '' '
+ 'UNION ALL '
+ 'SELECT ''----------------------------------------------------------------------------------------------------'' '
+ 'UNION ALL '
+ 'SELECT ''INSERT INTO @ColumnListWithActions VALUES ('' + CAST( ROW_NUMBER() OVER (ORDER BY [NAME]) as nvarchar(10)) + '', '' + '''''''' + [NAME] + ''''''''+ '', ''''S'''');'''
+ 'FROM [' + @DB_Name + '].sys.columns '
+ 'WHERE object_id = object_id(''[' + @DB_Name + ']..[' + @TableName + ']'') '
+ 'UNION ALL '
+ 'SELECT ''----------------------------------------------------------------------------------------------------'' '
+ 'UNION ALL '
+ 'SELECT ''-----| Execute sp_PivotExecute with parameters: columns and dimentions and main table name'' '
+ 'UNION ALL '
+ 'SELECT ''----------------------------------------------------------------------------------------------------'' '
+ 'UNION ALL '
+ 'SELECT ''EXEC [dbo].[sp_PivotExecute] @ColumnListWithActions, ' + '''''' + @TableName + '''''' + ';'''
+ 'UNION ALL '
+ 'SELECT ''----------------------------------------------------------------------------------------------------'' '
EXECUTE SP_EXECUTESQL @SQL_Code;
GO
CREATE PROCEDURE [dbo].[proc_PivotExecute]
(
@ColumnListWithActions ColumnActionList ReadOnly
,@TableName nvarchar(128)
)
AS
--#######################################################################################################################
--###| Author: Bartosz
--#######################################################################################################################
--#######################################################################################################################
--###| Step 1 - Select our user-defined-table-variable into temp table
--#######################################################################################################################
IF OBJECT_ID('tempdb.dbo.#ColumnListWithActions', 'U') IS NOT NULL DROP TABLE #ColumnListWithActions;
SELECT * INTO #ColumnListWithActions FROM @ColumnListWithActions;
--#######################################################################################################################
--###| Step 2 - Preparing lists of column groups as strings:
--#######################################################################################################################
DECLARE @ColumnName nvarchar(128)
DECLARE @Destiny nchar(1)
DECLARE @ListOfColumns_Stable nvarchar(max)
DECLARE @ListOfColumns_Dimension nvarchar(max)
DECLARE @ListOfColumns_Variable nvarchar(max)
--############################
--###| Cursor for List of Stable Columns
--############################
DECLARE ColumnListStringCreator_S CURSOR FOR
SELECT [ColumnName]
FROM #ColumnListWithActions
WHERE [Action] = 'S'
OPEN ColumnListStringCreator_S;
FETCH NEXT FROM ColumnListStringCreator_S
INTO @ColumnName
WHILE @@FETCH_STATUS = 0
BEGIN
SELECT @ListOfColumns_Stable = ISNULL(@ListOfColumns_Stable, '') + ' [' + @ColumnName + '] ,';
FETCH NEXT FROM ColumnListStringCreator_S INTO @ColumnName
END
CLOSE ColumnListStringCreator_S;
DEALLOCATE ColumnListStringCreator_S;
--############################
--###| Cursor for List of Dimension Columns
--############################
DECLARE ColumnListStringCreator_D CURSOR FOR
SELECT [ColumnName]
FROM #ColumnListWithActions
WHERE [Action] = 'D'
OPEN ColumnListStringCreator_D;
FETCH NEXT FROM ColumnListStringCreator_D
INTO @ColumnName
WHILE @@FETCH_STATUS = 0
BEGIN
SELECT @ListOfColumns_Dimension = ISNULL(@ListOfColumns_Dimension, '') + ' [' + @ColumnName + '] ,';
FETCH NEXT FROM ColumnListStringCreator_D INTO @ColumnName
END
CLOSE ColumnListStringCreator_D;
DEALLOCATE ColumnListStringCreator_D;
--############################
--###| Cursor for List of Variable Columns
--############################
DECLARE ColumnListStringCreator_V CURSOR FOR
SELECT [ColumnName]
FROM #ColumnListWithActions
WHERE [Action] = 'V'
OPEN ColumnListStringCreator_V;
FETCH NEXT FROM ColumnListStringCreator_V
INTO @ColumnName
WHILE @@FETCH_STATUS = 0
BEGIN
SELECT @ListOfColumns_Variable = ISNULL(@ListOfColumns_Variable, '') + ' [' + @ColumnName + '] ,';
FETCH NEXT FROM ColumnListStringCreator_V INTO @ColumnName
END
CLOSE ColumnListStringCreator_V;
DEALLOCATE ColumnListStringCreator_V;
SELECT @ListOfColumns_Variable = LEFT(@ListOfColumns_Variable, LEN(@ListOfColumns_Variable) - 1);
SELECT @ListOfColumns_Dimension = LEFT(@ListOfColumns_Dimension, LEN(@ListOfColumns_Dimension) - 1);
SELECT @ListOfColumns_Stable = LEFT(@ListOfColumns_Stable, LEN(@ListOfColumns_Stable) - 1);
--#######################################################################################################################
--###| Step 3 - Preparing table with all possible connections between Dimension columns excluding NULLs
--#######################################################################################################################
DECLARE @DIM_TAB TABLE ([DIM_ID] smallint, [ColumnName] nvarchar(128))
INSERT INTO @DIM_TAB
SELECT [DIM_ID] = ROW_NUMBER() OVER(ORDER BY [ColumnName]), [ColumnName] FROM #ColumnListWithActions WHERE [Action] = 'D';
DECLARE @DIM_ID smallint;
SELECT @DIM_ID = 1;
DECLARE @SQL_Dimentions nvarchar(max);
IF OBJECT_ID('tempdb.dbo.##ALL_Dimentions', 'U') IS NOT NULL DROP TABLE ##ALL_Dimentions;
SELECT @SQL_Dimentions = 'SELECT ID = ROW_NUMBER() OVER (ORDER BY ' + @ListOfColumns_Dimension + '), ' + @ListOfColumns_Dimension
+ ' INTO ##ALL_Dimentions '
+ ' FROM (SELECT DISTINCT' + @ListOfColumns_Dimension + ' FROM ' + @TableName
+ ' WHERE ' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = @DIM_ID) + ' IS NOT NULL ';
SELECT @DIM_ID = @DIM_ID + 1;
WHILE @DIM_ID <= (SELECT MAX([DIM_ID]) FROM @DIM_TAB)
BEGIN
SELECT @SQL_Dimentions = @SQL_Dimentions + 'AND ' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = @DIM_ID) + ' IS NOT NULL ';
SELECT @DIM_ID = @DIM_ID + 1;
END
SELECT @SQL_Dimentions = @SQL_Dimentions + ' )x';
EXECUTE SP_EXECUTESQL @SQL_Dimentions;
--#######################################################################################################################
--###| Step 4 - Preparing table with all possible connections between Stable columns excluding NULLs
--#######################################################################################################################
DECLARE @StabPos_TAB TABLE ([StabPos_ID] smallint, [ColumnName] nvarchar(128))
INSERT INTO @StabPos_TAB
SELECT [StabPos_ID] = ROW_NUMBER() OVER(ORDER BY [ColumnName]), [ColumnName] FROM #ColumnListWithActions WHERE [Action] = 'S';
DECLARE @StabPos_ID smallint;
SELECT @StabPos_ID = 1;
DECLARE @SQL_MainStableColumnTable nvarchar(max);
IF OBJECT_ID('tempdb.dbo.##ALL_StableColumns', 'U') IS NOT NULL DROP TABLE ##ALL_StableColumns;
SELECT @SQL_MainStableColumnTable = 'SELECT ID = ROW_NUMBER() OVER (ORDER BY ' + @ListOfColumns_Stable + '), ' + @ListOfColumns_Stable
+ ' INTO ##ALL_StableColumns '
+ ' FROM (SELECT DISTINCT' + @ListOfColumns_Stable + ' FROM ' + @TableName
+ ' WHERE ' + (SELECT [ColumnName] FROM @StabPos_TAB WHERE [StabPos_ID] = @StabPos_ID) + ' IS NOT NULL ';
SELECT @StabPos_ID = @StabPos_ID + 1;
WHILE @StabPos_ID <= (SELECT MAX([StabPos_ID]) FROM @StabPos_TAB)
BEGIN
SELECT @SQL_MainStableColumnTable = @SQL_MainStableColumnTable + 'AND ' + (SELECT [ColumnName] FROM @StabPos_TAB WHERE [StabPos_ID] = @StabPos_ID) + ' IS NOT NULL ';
SELECT @StabPos_ID = @StabPos_ID + 1;
END
SELECT @SQL_MainStableColumnTable = @SQL_MainStableColumnTable + ' )x';
EXECUTE SP_EXECUTESQL @SQL_MainStableColumnTable;
--#######################################################################################################################
--###| Step 5 - Preparing table with all options ID
--#######################################################################################################################
DECLARE @FULL_SQL_1 NVARCHAR(MAX)
SELECT @FULL_SQL_1 = ''
DECLARE @i smallint
IF OBJECT_ID('tempdb.dbo.##FinalTab', 'U') IS NOT NULL DROP TABLE ##FinalTab;
SELECT @FULL_SQL_1 = 'SELECT t.*, dim.[ID] '
+ ' INTO ##FinalTab '
+ 'FROM ' + @TableName + ' t '
+ 'JOIN ##ALL_Dimentions dim '
+ 'ON t.' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = 1) + ' = dim.' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = 1);
SELECT @i = 2
WHILE @i <= (SELECT MAX([DIM_ID]) FROM @DIM_TAB)
BEGIN
SELECT @FULL_SQL_1 = @FULL_SQL_1 + ' AND t.' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = @i) + ' = dim.' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = @i)
SELECT @i = @i +1
END
EXECUTE SP_EXECUTESQL @FULL_SQL_1
--#######################################################################################################################
--###| Step 6 - Selecting final data
--#######################################################################################################################
DECLARE @STAB_TAB TABLE ([STAB_ID] smallint, [ColumnName] nvarchar(128))
INSERT INTO @STAB_TAB
SELECT [STAB_ID] = ROW_NUMBER() OVER(ORDER BY [ColumnName]), [ColumnName]
FROM #ColumnListWithActions WHERE [Action] = 'S';
DECLARE @VAR_TAB TABLE ([VAR_ID] smallint, [ColumnName] nvarchar(128))
INSERT INTO @VAR_TAB
SELECT [VAR_ID] = ROW_NUMBER() OVER(ORDER BY [ColumnName]), [ColumnName]
FROM #ColumnListWithActions WHERE [Action] = 'V';
DECLARE @y smallint;
DECLARE @x smallint;
DECLARE @z smallint;
DECLARE @FinalCode nvarchar(max)
SELECT @FinalCode = ' SELECT ID1.*'
SELECT @y = 1
WHILE @y <= (SELECT MAX([ID]) FROM ##FinalTab)
BEGIN
SELECT @z = 1
WHILE @z <= (SELECT MAX([VAR_ID]) FROM @VAR_TAB)
BEGIN
SELECT @FinalCode = @FinalCode + ', [ID' + CAST((@y) as varchar(10)) + '.' + (SELECT [ColumnName] FROM @VAR_TAB WHERE [VAR_ID] = @z) + '] = ID' + CAST((@y + 1) as varchar(10)) + '.' + (SELECT [ColumnName] FROM @VAR_TAB WHERE [VAR_ID] = @z)
SELECT @z = @z + 1
END
SELECT @y = @y + 1
END
SELECT @FinalCode = @FinalCode +
' FROM ( SELECT * FROM ##ALL_StableColumns)ID1';
SELECT @y = 1
WHILE @y <= (SELECT MAX([ID]) FROM ##FinalTab)
BEGIN
SELECT @x = 1
SELECT @FinalCode = @FinalCode
+ ' LEFT JOIN (SELECT ' + @ListOfColumns_Stable + ' , ' + @ListOfColumns_Variable
+ ' FROM ##FinalTab WHERE [ID] = '
+ CAST(@y as varchar(10)) + ' )ID' + CAST((@y + 1) as varchar(10))
+ ' ON 1 = 1'
WHILE @x <= (SELECT MAX([STAB_ID]) FROM @STAB_TAB)
BEGIN
SELECT @FinalCode = @FinalCode + ' AND ID1.' + (SELECT [ColumnName] FROM @STAB_TAB WHERE [STAB_ID] = @x) + ' = ID' + CAST((@y+1) as varchar(10)) + '.' + (SELECT [ColumnName] FROM @STAB_TAB WHERE [STAB_ID] = @x)
SELECT @x = @x +1
END
SELECT @y = @y + 1
END
SELECT * FROM ##ALL_Dimentions;
EXECUTE SP_EXECUTESQL @FinalCode;
--#######################################################################################################################
从执行第一个查询（通过传递源数据库和表名），您将获得第二个SP的预先创建的执行查询，您所要做的就是定义来自您的源的列：+ Stable + Value（将使用基于那个集中值+）Dim（你想用来转动的列）
将自动定义名称和数据类型！
我不能在任何生产环境中推荐它，但是为adhoc BI请求做了工作。
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