sql - 在 SQL Server 2008 中获取 3 个表，避免使用两个循环和动态 SQL

我想从一个名为@X_Table 的表中获取3 个表(此表具有原始表 的列名)SQL 2008:

原始表有很多行和 5 个属性(我可以有更多属性，比如 30，但在这个例子中我有 5 个属性):

x1  x2   x3   x4   x5    
----------------------------
438 498  3625 3645 5000
438 498  3625 3648 5000
438 498  3625 3629 5000
437 501  3625 3626 5000
438 498  3626 3629 5000
439 498  3626 3629 5000
440 5000 3627 3628 5000
444 5021 3631 3634 5000
451 5025 3635 3639 5000
458 5022 3640 3644 5000
465 525  3646 3670 5000
473 533  3652 3676 5000
481 544  3658 3678 5000
484 544  3661 3665 5000
484 532  3669 3662 2945
482 520  3685 3664 2952
481 522  3682 3661 2955
480 525  3694 3664 2948
481 515  5018 3664 2956
479 5000 3696 3661 2953 
**...(EVEN MORE ROWS LIKE 100,000)** ...

首先，我在其他表中获取列的名称(var @table_name 指的是上面的表):

INSERT  @X_Table (ID,NAME) 
SELECT  [ID] = ORDINAL_POSITION, [NAME] = COLUMN_NAME 
        FROM INFORMATION_SCHEMA.COLUMNS 
        WHERE TABLE_NAME = @table_name

所以我得到了@X_Table:

@X_Table:

ID  NAME
------------
1   x1
2   x2
3   x3
4   x4
5   x5

然后对于每一列我想要该列中所有值的总和 所以 xi 中的所有值，所以总和(x1)、总和(x2)、总和(x3)、总和(x4)、总和(x5)`

表 1:INT、VARCHAR、FLOAT

ID Name  value
---------------------------
1   x1  48431
2   x2  138420
3   x3  192071
4   x4  192041
5   x5  204602

然后对于每一列我想要该列中所有值的总和乘以每一列例如
对于 x1 列:sum(x1*x1)、sum(x1*x2)、sum(x1*x3)、sum(x1*x4)、sum(x1*x5)
对于 x2 列:sum(x2*x2)、sum(x2*x3)、sum(x2*x4)、sum(x2*x5)
对于 x3 列:sum(x3*x3)、sum(x3*x4)、sum(x3*x5)
对于 x4 列:sum(x4*x4), sum(x4*x5)
对于 x5 列:sum(x5*x5)

表 2:INT、VARCHAR、FLOAT

ID   Name     value
---------------------------
1   SUM(x1*x1)  83926421
2   SUM(x1*x2)  162997894
3   SUM(x1*x3)  186865166
4   SUM(x1*x4)  156224385
5   SUM(x1*x5)  168573557
6   SUM(x2*x2)  598228836
7   SUM(x2*x3)  542331010
8   SUM(x2*x4)  460990820
9   SUM(x2*x5)  512335365
10  SUM(x3*x3)  797430261
11  SUM(x3*x4)  659040569
12  SUM(x3*x5)  723779398
13  SUM(x4*x4)  677091478
14  SUM(x4*x5)  722922237
15  SUM(x5*x5)  808976398

然后对于最后一个表，我想要对角线，或者在其他表中的 xii

表 3:INT、VARCHAR、FLOAT

ID   Name     value
---------------------------
1   SUM(x1*x1)  83926421
2   SUM(x2*x2)  598228836
3   SUM(x3*x3)  797430261
4   SUM(x4*x4)  677091478
5   SUM(x5*x5)  808976398

所以为了做到这一点，我正在采用这种方法，但我知道这可以优化，

SET @d = 5
WHILE (@counterI <= @d) BEGIN
        SELECT @nameThird   = NAME  FROM @X_Table where ID =  @counterI;
        SET    @nameFirst   = @nameThird;

    --INSERT FIRST TABLE
    SET @queryFirst = 'INSERT #FIRST_T (ID,NAME,Value) SELECT '+ CAST(@counterI AS VARCHAR)+' , '''+@nameFirst+''', SUM('+@nameFirst+') FROM '+ @table_name;
    EXEC (@queryFirst);

    --GET VALUE TO INSERT IN THIRD TABLE       
    SET @queryThird = 'INSERT #THIRD_T (ID,NAME,Value) SELECT '+CAST(@counterI AS VARCHAR)+' , '''+@nameThird+'*'+@nameThird+''', SUM('+@nameThird +'*'+@nameThird+') FROM '+  @table_name;
    EXEC (@queryThird);

    --Xij  
    WHILE (@counterJ <= @d) BEGIN           
        SELECT @nameThird2  = NAME  FROM @X_Table where ID =  @counterJ;
        SET @queryThird = 'INSERT #SECOND_T (ID,NAME,Value) SELECT '+CAST(@n AS VARCHAR)+' , '''+@nameThird+'*'+@nameThird2+''', SUM('+@nameThird +'*'+@nameThird2+') FROM '+  @table_name;
        EXEC (@queryThird);         
        SET @counterJ  = @counterJ + 1; 
        SET @n = @n +1  
    END         
    SET @counterI   = @counterI + 1; --reduce space
    SET @counterJ   = @counterI;
END

如果没有这 2 个，你会怎么做循环？，

(超过30个属性的表要花很多时间...)

----------------------------编辑------------ --------------

当列数超过 10 列时，我将获得 @table1(@Thomas 的回答)

ID 名称值

1   x1  8029145
2   x10 15453498
3   x11 13909514
4   x12 11336348
5   x13 11598240
6   x14 11951291
7   x15 12034693
8   x16 6558719
9   x17 5400520
10  x18 4966450
11  x19 5773049
12  x2  12696346
13  x20 5872404
14  x21 5542875
15  x22 9700954
16  x23 8484327
17  x24 8612340
18  x25 129470
19  x3  135818770

有什么方法可以按名字排序吗

x1,x2,x3,x4,x5...,x9,x10,x11....

代替

x1,x10,x11,x19,x2,x3....?

所以我们得到

ID Name Value
 -----------------
    1   x1  8029145
    2   x2  12696346
    3   x3  135818770
    ...

最佳答案

(扩展源数据以说明序号的使用)

如果将结构标准化，这个问题就容易多了。由于您正在尝试对列进行算术运算，因此它们需要是行而不是列。

Declare @X_Table Table
    (
    Id int not null Identity(1,1) Primary Key
    , x1 float not null
    , x2 float not null
    , x3 float not null
    , x4 float not null
    , x5 float not null
    , x111 float not null
    , x112 float not null
    , x113 float not null
    , x114 float not null
    , x115 float not null
    , x11 float not null
    , x12 float not null
    , x13 float not null
    , x14 float not null
    , x15 float not null
    )

Insert @X_Table( x1, x2, x3, x4, x5
    , x111, x112, x113, x114, x115 
    , x11, x12, x13, x14, x15 
    )
Select 438, 498, 3625, 3645, 5000, 438, 498, 3625, 3645, 5000, 438, 498, 3625, 3645, 5000
Union All Select 438, 498, 3625, 3648, 5000, 438, 498, 3625, 3648, 5000, 438, 498, 3625, 3648, 5000
Union All Select 438, 498, 3625, 3629, 5000, 438, 498, 3625, 3629, 5000, 438, 498, 3625, 3629, 5000
Union All Select 437, 501, 3625, 3626, 5000, 437, 501, 3625, 3626, 5000, 437, 501, 3625, 3626, 5000
Union All Select 438, 498, 3626, 3629, 5000, 438, 498, 3626, 3629, 5000, 438, 498, 3626, 3629, 5000
Union All Select 439, 498, 3626, 3629, 5000, 439, 498, 3626, 3629, 5000, 439, 498, 3626, 3629, 5000
Union All Select 440, 5000, 3627, 3628, 5000, 440, 5000, 3627, 3628, 5000, 440, 5000, 3627, 3628, 5000
Union All Select 444, 5021, 3631, 3634, 5000, 444, 5021, 3631, 3634, 5000, 444, 5021, 3631, 3634, 5000
Union All Select 451, 5025, 3635, 3639, 5000, 451, 5025, 3635, 3639, 5000, 451, 5025, 3635, 3639, 5000
Union All Select 458, 5022, 3640, 3644, 5000, 458, 5022, 3640, 3644, 5000, 458, 5022, 3640, 3644, 5000
Union All Select 465, 525, 3646, 3670, 5000, 465, 525, 3646, 3670, 5000, 465, 525, 3646, 3670, 5000
Union All Select 473, 533, 3652, 3676, 5000, 473, 533, 3652, 3676, 5000, 473, 533, 3652, 3676, 5000
Union All Select 481, 544, 3658, 3678, 5000, 481, 544, 3658, 3678, 5000, 481, 544, 3658, 3678, 5000
Union All Select 484, 544, 3661, 3665, 5000, 484, 544, 3661, 3665, 5000, 484, 544, 3661, 3665, 5000
Union All Select 484, 532, 3669, 3662, 2945, 484, 532, 3669, 3662, 2945, 484, 532, 3669, 3662, 2945
Union All Select 482, 520, 3685, 3664, 2952, 482, 520, 3685, 3664, 2952, 482, 520, 3685, 3664, 2952
Union All Select 481, 522, 3682, 3661, 2955, 481, 522, 3682, 3661, 2955, 481, 522, 3682, 3661, 2955
Union All Select 480, 525, 3694, 3664, 2948, 480, 525, 3694, 3664, 2948, 480, 525, 3694, 3664, 2948
Union All Select 481, 515, 5018, 3664, 2956, 481, 515, 5018, 3664, 2956, 481, 515, 5018, 3664, 2956
Union All Select 479, 5000, 3696, 3661, 2953, 479, 5000, 3696, 3661, 2953, 479, 5000, 3696, 3661, 2953

下表显然是静态的。但是，如果您要涉及动态 SQL(在 T-SQL 中不推荐，但显然可行)，下一张表的填充将是唯一的部分。

Declare @X_Table_Normalized Table
    (
    Id int not null
    , Ordinal int not null
    , Name varchar(10) not null
    , Value float not null
    )

Insert @X_Table_Normalized( Id, Ordinal, Name, Value )
Select Id, 1, 'x1', x1 From @X_Table
Union All Select Id, 2, 'x2', x2 From @X_Table
Union All Select Id, 3, 'x3', x3 From @X_Table
Union All Select Id, 4, 'x4', x4 From @X_Table
Union All Select Id, 5, 'x5', x5 From @X_Table
Union All Select Id, 6, 'x111', x111 From @X_Table
Union All Select Id, 7, 'x112', x112 From @X_Table
Union All Select Id, 8, 'x113', x113 From @X_Table
Union All Select Id, 9, 'x114', x114 From @X_Table
Union All Select Id, 10, 'x115', x115 From @X_Table
Union All Select Id, 11, 'x11', x11 From @X_Table
Union All Select Id, 12, 'x12', x12 From @X_Table
Union All Select Id, 13, 'x13', x13 From @X_Table
Union All Select Id, 14, 'x14', x14 From @X_Table
Union All Select Id, 15, 'x15', x15 From @X_Table

表 1 - 按(原始)列求和

Declare @Table1 Table
    (
    Id int not null
    , Name varchar(25) not null
    , Ordinal int not null
    , Value float not null
    )

Insert @Table1( Id, Name, Ordinal, Value )
Select Row_Number() Over( Order By Ordinal, Name )
    , Name, Ordinal, Sum(Value)
From @X_Table_Normalized
Group By Ordinal, Name

表 2 - 按(原始)列的产品总和

Declare @Table2 Table
    (
    Id int not null
    , Name varchar(25) not null
    , Ordinal int not null
    , Value float not null
    )

Insert @Table2( Id, Name, Ordinal, Value )
Select Row_Number() Over ( Order By T1.Ordinal, T1.Name, T2.Ordinal, T2.Name ) As Id
    , 'Sum(' + T1.Name + '*' + T2.Name + ')' As Name
    , T1.Ordinal + 100 * T2.Ordinal
    , Sum( T1.Value * T2.Value ) As Value
From @X_Table_Normalized As T1
    Join @X_Table_Normalized As T2
        On T2.Id = T1.Id
Where T1.Ordinal <= T2.Ordinal
Group By T1.Name, T1.Ordinal, T2.Name, T2.Ordinal

表 3 - 按(原始)列对角线的乘积和

Declare @Table3 Table
    (
    Id int not null
    , Name varchar(25) not null
    , Ordinal int not null
    , Value float not null
    )

Insert @Table3( Id, Name, Ordinal, Value )
Select Row_Number() Over ( Order By T1.Ordinal, T1.Name, T2.Ordinal, T2.Name ) As Id
    , 'Sum(' + T1.Name + '*' + T2.Name + ')' As Name
    , T1.Ordinal + 100 * T2.Ordinal
    , Sum( T1.Value * T2.Value ) As Value
From @X_Table_Normalized As T1
    Join @X_Table_Normalized As T2
        On T2.Id = T1.Id
Where T1.Ordinal = T2.Ordinal
Group By T1.Name, T1.Ordinal, T2.Name, T2.Ordinal

Select * From @Table1 Order By Ordinal
Select * From @Table2 Order By Ordinal
Select * From @Table3 Order By Ordinal

使用动态 SQL 填充规范化表

根据它的使用方式，您可以使用动态 SQL 封装规范化表的填充。如果这样做，您将需要使用真实表或临时表而不是临时变量。该代码可能类似于:

Declare @Sql nvarchar(max)

Set @Sql = 'Insert #X_Table_Normalized_Dynamic( Id, Ordinal, Name, Value )|'
Select @Sql = @Sql + ' Union All Select Id'
    + ', ' + Cast( Row_Number() Over ( Order By ORDINAL_POSITION ) As varchar(10) )
    + ', ' + QuoteName(COLUMN_NAME, '''')
    + ', ' + QuoteName(COLUMN_NAME)
From INFORMATION_SCHEMA.COLUMNS
Where TABLE_NAME = 'MySourceTable'

Set @Sql = Replace( @Sql, '| Union All ', ' ')

Exec( @Sql )

关于sql - 在 SQL Server 2008 中获取 3 个表，避免使用两个循环和动态 SQL，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/5873542/

sql - 在 SQL Server 2008 中获取 3 个表，避免使用两个循环和动态 SQL

表 1 - 按(原始)列求和

表 2 - 按(原始)列的产品总和

表 3 - 按(原始)列对角线的乘积和

使用动态 SQL 填充规范化表

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