事实表中的外键参照完整性 - T-SQL

Question

我有这个事实table:

CREATE TABLE [dbo].[FACT_TABLE]
(
    [A_id] [int] NOT NULL,
    [B_id] [int] NOT NULL,
    [C_id] [int] NOT NULL,
    [D_id] [int] NOT NULL,
    [FACT_total] [float] NOT NULL,
    [FACT_average] [float] NOT NULL,

    CONSTRAINT [PK_FACT_TABLE] 
        PRIMARY KEY CLUSTERED ([A_id] ASC, [B_id] ASC,
                               [C_id] ASC, [D_id] ASC)
) ON [PRIMARY]

我有一个 T-SQL 脚本来将数据加载到我的事实中 table:

INSERT INTO [dbo].[FACT_TABLE] ([A_id], [B_id], [C_id], [company_id], [D_id],[FACT_total], [FACT_average])
    SELECT 
        b.A_id, c.B_id, d.C_id, e.D_id,
        AVG(FACT_total) AS FACT_total,
        AVG(FACT_average) AS FACT_average
    FROM 
        [dbo].[staging_Area] a
    INNER JOIN 
        [dbo].[DIM_A] b ON a.A_id = b.A_id
    INNER JOIN 
        [dbo].[DIM_B] c ON a.[B_id] = c.B_id
    INNER JOIN 
        [dbo].[DIM_C] d ON a.[C_id] = d.C_id 
    INNER JOIN 
        [dbo].[DIM_D] e ON a.D_id = e.D_id
    GROUP BY  
        b.A_id, c.B_id, d.C_id, e.D_id

如何保证我不会在我的事实中插入重复值 table 以避免出现引用完整性错误？

我在该查询后尝试使用以下语句：

EXCEPT 
SELECT *
FROM [dbo].[FACT_TABLE]

但我认为这不是最好的方法...

有人对此有其他选择吗？抱歉，我不能输入真实的专栏和 table 的名字...

谢谢！

Answer 1

LEFT OUTER JOIN 与 WHERE FT.Column IS NULL 到事实 table 以确保您没有插入已存在的记录：

INSERT INTO [dbo].[FACT_TABLE] ([A_id],[B_id],[C_id],[company_id],[D_id],[FACT_total],[FACT_average])
SELECT b.A_id
        ,c.B_id
        ,d.C_id
        ,e.D_id
        ,AVG(FACT_total) AS FACT_total
        ,AVG(FACT_average) AS FACT_average
FROM [dbo].[staging_Area] a
INNER JOIN [dbo].[DIM_A] b ON
    a.A_id = b.A_id
INNER JOIN [dbo].[DIM_B] c ON
    a.[B_id] = c.B_id
INNER JOIN [dbo].[DIM_C] d ON
    a.[C_id] = d.C_id 
INNER JOIN [dbo].[DIM_D] e ON
    a.D_id = e.D_id
LEFT OUTER JOIN dbo.[FACT_TABLE] FT
    ON b.A_ID = FT.A_id
    AND c.B_id = FT.B_id
    AND D.C_ID = FT.C_id
    AND E.D_id = FT.D_id
WHERE FT.A_ID IS NULL
GROUP BY  b.A_id
        ,c.B_id
        ,d.C_id
        ,e.D_id

Answer 2

插入 [dbo].[FACT_TABLE]

([A_id], [B_id], [C_id], [D_id],[FACT_total], [FACT_average])

select a.A_id, a.B_id, a.C_id, a.D_id,a.FACT_total,a.FACT_average

来自

( SELECT

b.A_id, c.B_id, d.C_id, e.D_id,
AVG(FACT_total) AS FACT_total,
AVG(FACT_average) AS FACT_average

来自

[dbo].[staging_Area] a

内连接

[dbo].[DIM_A] b ON a.A_id = b.A_id

内连接

[dbo].[DIM_B] c ON a.[B_id] = c.B_id

内连接 [dbo].[DIM_C] d ON a.[C_id] = d.C_id

内连接

[dbo].[DIM_D] e ON a.D_id = e.D_id

分组依据

b.A_id, c.B_id, d.C_id, e.D_id 

)a

其中

不存在

( SELECT 1 来自 dbao.FACT_TABLE B

哪里
B.A_id = A.A_id AND B.B_id = A.B_id and b.C_id=a.C_id and b.D_id=a.D_id

事实表中的外键参照完整性 - T-SQL

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