SQL Server动态枢轴查询？

Question

我的任务是提出一种翻译以下数据的方法：

date        category        amount
1/1/2012    ABC             1000.00
2/1/2012    DEF             500.00
2/1/2012    GHI             800.00
2/10/2012   DEF             700.00
3/1/2012    ABC             1100.00

为以下内容：

date        ABC             DEF             GHI
1/1/2012    1000.00
2/1/2012                    500.00
2/1/2012                                    800.00
2/10/2012                   700.00
3/1/2012    1100.00

空白点可以为空或空白，要么很好，而且类别需要动态。另一个可能的警告是，我们将以有限的容量运行查询，这意味着临时表已算出。我已经尝试研究并登陆了pivot，但是尽管我尽了最大的努力来弄清楚它，但我从未真正使用过它。谁能向我指向正确的方向？

Answer 1

动态SQL枢轴：

create table temp
(
    date datetime,
    category varchar(3),
    amount money
)

insert into temp values ('1/1/2012', 'ABC', 1000.00)
insert into temp values ('2/1/2012', 'DEF', 500.00)
insert into temp values ('2/1/2012', 'GHI', 800.00)
insert into temp values ('2/10/2012', 'DEF', 700.00)
insert into temp values ('3/1/2012', 'ABC', 1100.00)


DECLARE @cols AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX);

SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(c.category) 
            FROM temp c
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')
    
set @query = 'SELECT date, ' + @cols + ' from 
            (
                select date
                    , amount
                    , category
                from temp
           ) x
            pivot 
            (
                 max(amount)
                for category in (' + @cols + ')
            ) p '


execute(@query)

drop table temp

结果：

Date                        ABC         DEF    GHI
2012-01-01 00:00:00.000     1000.00     NULL    NULL
2012-02-01 00:00:00.000     NULL        500.00  800.00
2012-02-10 00:00:00.000     NULL        700.00  NULL
2012-03-01 00:00:00.000     1100.00     NULL    NULL

Answer 2

动态SQL枢轴

创建列的不同方法字符串

create table #temp
(
    date datetime,
    category varchar(3),
    amount money
)

insert into #temp values ('1/1/2012', 'ABC', 1000.00)
insert into #temp values ('2/1/2012', 'DEF', 500.00)
insert into #temp values ('2/1/2012', 'GHI', 800.00)
insert into #temp values ('2/10/2012', 'DEF', 700.00)
insert into #temp values ('3/1/2012', 'ABC', 1100.00)

DECLARE @cols  AS NVARCHAR(MAX)='';
DECLARE @query AS NVARCHAR(MAX)='';

SELECT @cols = @cols + QUOTENAME(category) + ',' FROM (select distinct category from #temp ) as tmp
select @cols = substring(@cols, 0, len(@cols)) --trim "," at end

set @query = 
'SELECT * from 
(
    select date, amount, category from #temp
) src
pivot 
(
    max(amount) for category in (' + @cols + ')
) piv'

execute(@query)
drop table #temp

结果

date                    ABC     DEF     GHI
2012-01-01 00:00:00.000 1000.00 NULL    NULL
2012-02-01 00:00:00.000 NULL    500.00  800.00
2012-02-10 00:00:00.000 NULL    700.00  NULL
2012-03-01 00:00:00.000 1100.00 NULL    NULL

Answer 3

我知道这个问题年龄较大，但我正在通过答案来寻找我的问题，并认为我可能能够扩展问题的“动态”部分，并可能帮助某人。

首先，我建立了这个解决方案来解决一个问题，几个同事遇到了不一致和大型数据集，需要快速枢转。

该解决方案需要创建存储过程，因此，如果您的需求不满意，请立即停止阅读。

此过程将采用Pivot语句的关键变量，以动态创建不同表，列名和聚合的枢轴语句。静态列被用作枢轴的组 /身份列（如果不需要的话，可以从代码中删除，但在枢轴语句中很常见，并且是解决原始问题的必要条件），枢轴列是最终结果列名将是从中生成的，值列是将汇总应用到的。表参数是表的名称，包括架构（schema.tablename）此部分可以使用某些爱，因为它不像我想要的那样干净。它对我有用，因为我的用法不是公开面对的，而SQL注入也不关心。汇总参数将接受任何标准的SQL汇总“ AVG”，“ sum”，“ max”等。代码还默认为Max作为汇总，这不是必需的，但是最初为此构建的受众群体不了解枢轴，并且通常是将MAX用作汇总。

让我们从代码开始以创建存储过程。该代码应在所有版本的SSM 2005及更高版本中使用，但我尚未在2005年或2016年对其进行测试，但我看不出为什么它不起作用。

create PROCEDURE [dbo].[USP_DYNAMIC_PIVOT]
    (
        @STATIC_COLUMN VARCHAR(255),
        @PIVOT_COLUMN VARCHAR(255),
        @VALUE_COLUMN VARCHAR(255),
        @TABLE VARCHAR(255),
        @AGGREGATE VARCHAR(20) = null
    )

AS


BEGIN

SET NOCOUNT ON;
declare @AVAIABLE_TO_PIVOT NVARCHAR(MAX),
        @SQLSTRING NVARCHAR(MAX),
        @PIVOT_SQL_STRING NVARCHAR(MAX),
        @TEMPVARCOLUMNS NVARCHAR(MAX),
        @TABLESQL NVARCHAR(MAX)

if isnull(@AGGREGATE,'') = '' 
    begin
        SET @AGGREGATE = 'MAX'
    end


 SET @PIVOT_SQL_STRING =    'SELECT top 1 STUFF((SELECT distinct '', '' + CAST(''[''+CONVERT(VARCHAR,'+ @PIVOT_COLUMN+')+'']''  AS VARCHAR(50)) [text()]
                            FROM '+@TABLE+'
                            WHERE ISNULL('+@PIVOT_COLUMN+','''') <> ''''
                            FOR XML PATH(''''), TYPE)
                            .value(''.'',''NVARCHAR(MAX)''),1,2,'' '') as PIVOT_VALUES
                            from '+@TABLE+' ma
                            ORDER BY ' + @PIVOT_COLUMN + ''

declare @TAB AS TABLE(COL NVARCHAR(MAX) )

INSERT INTO @TAB EXEC SP_EXECUTESQL  @PIVOT_SQL_STRING, @AVAIABLE_TO_PIVOT 

SET @AVAIABLE_TO_PIVOT = (SELECT * FROM @TAB)


SET @TEMPVARCOLUMNS = (SELECT replace(@AVAIABLE_TO_PIVOT,',',' nvarchar(255) null,') + ' nvarchar(255) null')


SET @SQLSTRING = 'DECLARE @RETURN_TABLE TABLE ('+@STATIC_COLUMN+' NVARCHAR(255) NULL,'+@TEMPVARCOLUMNS+')  
                    INSERT INTO @RETURN_TABLE('+@STATIC_COLUMN+','+@AVAIABLE_TO_PIVOT+')

                    select * from (
                    SELECT ' + @STATIC_COLUMN + ' , ' + @PIVOT_COLUMN + ', ' + @VALUE_COLUMN + ' FROM '+@TABLE+' ) a

                    PIVOT
                    (
                    '+@AGGREGATE+'('+@VALUE_COLUMN+')
                    FOR '+@PIVOT_COLUMN+' IN ('+@AVAIABLE_TO_PIVOT+')
                    ) piv

                    SELECT * FROM @RETURN_TABLE'



EXEC SP_EXECUTESQL @SQLSTRING

END

接下来，我们将为示例准备好数据。我从接受的答案中添加了几个数据元素，以在此概念验证中使用数据示例，以显示汇总变化的各种输出。

create table temp
(
    date datetime,
    category varchar(3),
    amount money
)

insert into temp values ('1/1/2012', 'ABC', 1000.00)
insert into temp values ('1/1/2012', 'ABC', 2000.00) -- added
insert into temp values ('2/1/2012', 'DEF', 500.00)
insert into temp values ('2/1/2012', 'DEF', 1500.00) -- added
insert into temp values ('2/1/2012', 'GHI', 800.00)
insert into temp values ('2/10/2012', 'DEF', 700.00)
insert into temp values ('2/10/2012', 'DEF', 800.00) -- addded
insert into temp values ('3/1/2012', 'ABC', 1100.00)

以下示例显示了不同的执行语句，显示了各种聚合作为一个简单的示例。我没有选择更改静态，枢轴和值列以使示例保持简单。您应该能够仅复制和粘贴代码即可自己开始处理此

exec [dbo].[USP_DYNAMIC_PIVOT] 'date','category','amount','dbo.temp','sum'
exec [dbo].[USP_DYNAMIC_PIVOT] 'date','category','amount','dbo.temp','max'
exec [dbo].[USP_DYNAMIC_PIVOT] 'date','category','amount','dbo.temp','avg'
exec [dbo].[USP_DYNAMIC_PIVOT] 'date','category','amount','dbo.temp','min'

执行，分别返回以下数据集。

Answer 4

SQL Server 2017的更新版本使用String_agg函数来构造枢轴列列表：

create table temp
(
    date datetime,
    category varchar(3),
    amount money
);

insert into temp values ('20120101', 'ABC', 1000.00);
insert into temp values ('20120201', 'DEF', 500.00);
insert into temp values ('20120201', 'GHI', 800.00);
insert into temp values ('20120210', 'DEF', 700.00);
insert into temp values ('20120301', 'ABC', 1100.00);


DECLARE @cols AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX);

SET @cols = (SELECT STRING_AGG(category,',') FROM (SELECT DISTINCT category FROM temp WHERE category IS NOT NULL)t);

set @query = 'SELECT date, ' + @cols + ' from 
            (
                select date
                    , amount
                    , category
                from temp
           ) x
            pivot 
            (
                 max(amount)
                for category in (' + @cols + ')
            ) p ';

execute(@query);

drop table temp;

Answer 5

taryn的答案随着性能改进：

数据

CREATE TABLE dbo.Temp
(
    [date] datetime NOT NULL,
    category nchar(3) NOT NULL,
    amount money NOT NULL,

    INDEX [CX dbo.Temp date] CLUSTERED ([date]),
    INDEX [IX dbo.Temp category] NONCLUSTERED (category)
);

INSERT dbo.Temp
    ([date], category, amount)
VALUES
    ({D '2012-01-01'}, N'ABC', $1000.00),
    ({D '2012-01-02'}, N'DEF', $500.00),
    ({D '2012-01-02'}, N'GHI', $800.00),
    ({D '2012-02-10'}, N'DEF', $700.00),
    ({D '2012-03-01'}, N'ABC', $1100.00);

动态枢轴

DECLARE 
    @Delimiter nvarchar(4000) = N',',
    @DelimiterLength bigint,
    @Columns nvarchar(max),
    @Query nvarchar(max);

SET @DelimiterLength = LEN(REPLACE(@Delimiter, SPACE(1), N'#'));

-- Before SQL Server 2017
SET @Columns =
    STUFF
    (
        (
            SELECT 
                [text()] = @Delimiter,
                [text()] = QUOTENAME(T.category)
            FROM dbo.Temp AS T
            WHERE T.category IS NOT NULL
            GROUP BY T.category
            ORDER BY T.category
            FOR XML PATH (''), TYPE
        )
        .value(N'text()[1]', N'nvarchar(max)'),
        1, @DelimiterLength, SPACE(0)
    );

-- Alternative for SQL Server 2017+ and database compatibility level 110+
SELECT @Columns = 
    STRING_AGG(CONVERT(nvarchar(max), QUOTENAME(T.category)), N',')
        WITHIN GROUP (ORDER BY T.category)
FROM 
(
    SELECT T2.category
    FROM dbo.Temp AS T2
    WHERE T2.category IS NOT NULL
    GROUP BY T2.category
) AS T;

IF @Columns IS NOT NULL
BEGIN
    SET @Query = 
        N'SELECT [date], ' + 
        @Columns + 
        N' 
        FROM
        (
            SELECT [date], amount, category
            FROM dbo.Temp
        ) AS S
        PIVOT
        (
            MAX(amount)
            FOR category IN (' +
            @Columns +
            N')
        ) AS P;';

    EXECUTE sys.sp_executesql @Query;
END;

执行计划

结果

“ alt	/B8JKR.png“ rel =” noreferrer“> <	src =” https://i.sstatic.net/b8jkr.png	img
=“ dynamic pivot 01-01 00：00：00.000	1000.00	NULL	NULL
2012-01-02-02 00：00：00.000	NULL	500.00	800.00
2012-02-02-10 00：00：00.00.000.000	NAULL 700.00 NULL	700.00	NAULL
2012-03-03-03-01 00：00.00：00：00：00：00：00：00：00：00：00：00：00：	000.00	null Null Null Null	Null Null

Answer 6

以下代码提供了将 null 替换为零的结果。

表创建和数据插入：

create table test_table
 (
 date nvarchar(10),
 category char(3),
 amount money
 )

 insert into test_table values ('1/1/2012','ABC',1000.00)
 insert into test_table values ('2/1/2012','DEF',500.00)
 insert into test_table values ('2/1/2012','GHI',800.00)
 insert into test_table values ('2/10/2012','DEF',700.00)
 insert into test_table values ('3/1/2012','ABC',1100.00)

查询要生成确切的结果，该结果还用零代替NULL：

DECLARE @DynamicPivotQuery AS NVARCHAR(MAX),
@PivotColumnNames AS NVARCHAR(MAX),
@PivotSelectColumnNames AS NVARCHAR(MAX)

--Get distinct values of the PIVOT Column
SELECT @PivotColumnNames= ISNULL(@PivotColumnNames + ',','')
+ QUOTENAME(category)
FROM (SELECT DISTINCT category FROM test_table) AS cat

--Get distinct values of the PIVOT Column with isnull
SELECT @PivotSelectColumnNames 
= ISNULL(@PivotSelectColumnNames + ',','')
+ 'ISNULL(' + QUOTENAME(category) + ', 0) AS '
+ QUOTENAME(category)
FROM (SELECT DISTINCT category FROM test_table) AS cat

--Prepare the PIVOT query using the dynamic 
SET @DynamicPivotQuery = 
N'SELECT date, ' + @PivotSelectColumnNames + '
FROM test_table
pivot(sum(amount) for category in (' + @PivotColumnNames + ')) as pvt';

--Execute the Dynamic Pivot Query
EXEC sp_executesql @DynamicPivotQuery

output：

Answer 7

有我的解决方案正在清理未核心的零值

DECLARE @cols AS NVARCHAR(MAX),
@maxcols AS NVARCHAR(MAX),
@query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT ',' + QUOTENAME(CodigoFormaPago) 
                from PO_FormasPago
                order by CodigoFormaPago
        FOR XML PATH(''), TYPE
        ).value('.', 'NVARCHAR(MAX)') 
    ,1,1,'')

select @maxcols = STUFF((SELECT ',MAX(' + QUOTENAME(CodigoFormaPago) + ') as ' + QUOTENAME(CodigoFormaPago)
                from PO_FormasPago
                order by CodigoFormaPago
        FOR XML PATH(''), TYPE
        ).value('.', 'NVARCHAR(MAX)')
    ,1,1,'')

set @query = 'SELECT CodigoProducto, DenominacionProducto, ' + @maxcols + '
            FROM
            (
                SELECT 
                CodigoProducto, DenominacionProducto,
                ' + @cols + ' from 
                 (
                    SELECT 
                        p.CodigoProducto as CodigoProducto,
                        p.DenominacionProducto as DenominacionProducto,
                        fpp.CantidadCuotas as CantidadCuotas,
                        fpp.IdFormaPago as IdFormaPago,
                        fp.CodigoFormaPago as CodigoFormaPago
                    FROM
                        PR_Producto p
                        LEFT JOIN PR_FormasPagoProducto fpp
                            ON fpp.IdProducto = p.IdProducto
                        LEFT JOIN PO_FormasPago fp
                            ON fpp.IdFormaPago = fp.IdFormaPago
                ) xp
                pivot 
                (
                    MAX(CantidadCuotas)
                    for CodigoFormaPago in (' + @cols + ')
                ) p 
            )  xx 
            GROUP BY CodigoProducto, DenominacionProducto'

t @query;

execute(@query);

Answer 8

完全通用的方式将在非传统的MS SQL环境（例如Azure Synapse Analytics无服务器SQL池）中使用 - 它在Sproc中，但无需这样使用...

-- DROP PROCEDURE IF EXISTS
if object_id('dbo.usp_generic_pivot') is not null 
     DROP PROCEDURE dbo.usp_generic_pivot
GO;

CREATE PROCEDURE dbo.usp_generic_pivot (
    @source NVARCHAR (100), -- table or view object name
   @pivotCol NVARCHAR (100), -- the column to pivot
   @pivotAggCol NVARCHAR (100), -- the column with the values for the pivot
   @pivotAggFunc NVARCHAR (20), -- the aggregate function to apply to those values
   @leadCols NVARCHAR (100) -- comma seprated list of other columns to keep and order by
)
AS
BEGIN
   DECLARE @pivotedColumns NVARCHAR(MAX)
   DECLARE @tsql NVARCHAR(MAX)

   SET @tsql = CONCAT('SELECT @pivotedColumns = STRING_AGG(qname, '','') FROM (SELECT DISTINCT QUOTENAME(', @pivotCol,') AS qname FROM ',@source, ') AS qnames')
   EXEC sp_executesql @tsql, N'@pivotedColumns nvarchar(max) out', @pivotedColumns out

   SET @tsql = CONCAT ( 'SELECT ', @leadCols,   ',', @pivotedColumns,' FROM ',' ( SELECT ',@leadCols,',',
         @pivotAggCol,',',   @pivotCol,   ' FROM ',   @source,   ') as t ',
         ' PIVOT (', @pivotAggFunc,   '(', @pivotAggCol,   ')',' FOR ',   @pivotCol,
         '   IN (', @pivotedColumns,')) as pvt ',' ORDER BY ',   @leadCols)

   EXEC (@tsql)

END
GO;

-- TEST EXAMPLE
EXEC dbo.usp_generic_pivot  
    @source  = '[your_db].[dbo].[form_answers]',
   @pivotCol  = 'question', 
   @pivotAggCol   = 'answer',
   @pivotAggFunc  = 'MAX', 
   @leadCols    = 'candidate_id, candidate_name' 
GO;

Answer 9

CREATE TABLE #PivotExample(
   [ID]      [nvarchar](50)   NULL,       
   [Description]   [nvarchar](50)   NULL,
   [ClientId]   [smallint] NOT NULL,
)
GO


INSERT   #PivotExample  ([ID],[Description],   [ClientId])   VALUES ('ACI1','ACI1Desc1',1008)
INSERT   #PivotExample  ([ID],[Description],   [ClientId])   VALUES ('ACI1','ACI1Desc2',2000)
INSERT   #PivotExample  ([ID],[Description],   [ClientId])   VALUES ('ACI1','ACI1Desc3',3000)
INSERT   #PivotExample  ([ID],[Description],   [ClientId])   VALUES ('ACI1','ACI1Desc4',4000)
INSERT   #PivotExample  ([ID],[Description],   [ClientId])   VALUES ('ACI2','ACI2Desc1',5000)
INSERT   #PivotExample  ([ID],[Description],   [ClientId])   VALUES ('ACI2','ACI2Desc2',6000)
INSERT   #PivotExample  ([ID],[Description],   [ClientId])   VALUES ('ACI2','ACI2Desc3', 7000)

SELECT * FROM #PivotExample




--Declare necessary variables
DECLARE   @SQLQuery AS NVARCHAR(MAX)
DECLARE   @PivotColumns AS NVARCHAR(MAX)
 
--Get unique values of pivot column  
SELECT   @PivotColumns= COALESCE(@PivotColumns + ',','') + QUOTENAME([Description])
FROM (SELECT DISTINCT [Description] FROM [dbo].#PivotExample) AS PivotExample
 
--SELECT   @PivotColumns
 
--Create the dynamic query with all the values for 
--pivot column at runtime
SET   @SQLQuery = 
    N' -- Your pivoted result comes here
    SELECT ID, ' + @PivotColumns + '
    FROM 
    (
        -- Source table should in a inner query
        SELECT ID,[Description],[ClientId]
        FROM #PivotExample
    )AS P
    PIVOT
    (     
          -- Select the values from derived table P
          SUM(ClientId) 
          FOR [Description] IN (' + @PivotColumns + ') 
    )AS PVTTable'
 
--SELECT   @SQLQuery
--Execute dynamic query
EXEC sp_executesql @SQLQuery


Drop table #PivotExample