Question

我需要帮助。

我有一个与其他两个表t1和t3相关的sql表t2。

t2有字段：

idFromt3 idFromt1 Value

1        14        text1
2        14        text2
1        44        text1
2        44        text2
3        44        text3

我正在搜索缺少ifFromt3的值。我想在这个例子中使用值ifFromt3 = 3，因为它不存在。

我这样做就像这样，但它无法正常工作。

SELECT t3.idFromt3, t3.idFromt1
FROM t3 
  INNER JOIN t2 
    ON t3.LanguageMessageCodeID <> t2.idFromt2

这是3张桌子。

CREATE TABLE [dbo].[t3](
    [t3ID] [int] IDENTITY(1,1) NOT NULL,
    [Name] [varchar](50) NOT NULL,
)

CREATE TABLE [dbo].[t2](
    [t2ID] [int] IDENTITY(1,1) NOT NULL,
    [t3ID] [int] NOT NULL,
    [t1ID] [int] NOT NULL,
)


CREATE TABLE [dbo].[t1](
    [t1ID] [int] IDENTITY(1,1) NOT NULL,
    [Name] [varchar](50) NOT NULL,
)

更新：

包含数据的表格： http://www.2shared.com/photo/40yY6FC-/Untitled.html

我需要一个查询，它返回表LangugageMessageCodes中所有缺少的组合。

在这种情况下：

LanguageMessageCodeID  LanguageID
3                      14
1                      47
2                      47
3                      47

请。帮助

问候。

Answer 1

如果要查找连接表中不的行，则需要使用LEFT OUTER JOIN。

外部联接将导致左表的所有行，无论是否与右表匹配。

为了过滤那些不存在的子句，您可以为正确的表格添加WHERE子句检查NULL值。

SELECT t3.idFromt3, t3.idFromt1
FROM t3 
  LEFT OUTER JOIN t2 
    ON t3.LanguageMessageCodeID <> t2.idFromt2
WHERE t2.idFromts IS NULL

Answer 2

SELECT  *
FROM    t2
WHERE   t2.idFromt3 NOT IN
        (
        SELECT  LanguageMessageCodeID
        FROM    t3
        )

或

SELECT  *
FROM    t2
WHERE   NOT EXISTS
        (
        SELECT  NULL
        FROM    t3
        WHERE   t3.LanguageMessageCodeID = t2.id
        )

或

SELECT  t2.*
FROM    t2
LEFT JOIN
        t3
ON      t3.LanguageMessageCodeID = t2.id
WHERE   t3.LanguageMessageCodeID IS NULL

<强>更新

试试这个：

SET NOCOUNT ON
DECLARE @t1 TABLE (id INT NOT NULL PRIMARY KEY)
DECLARE @t2 TABLE (t3id INT NOT NULL, t1id INT NOT NULL, PRIMARY KEY (t1id, t3id))
DECLARE @t3 TABLE (id INT NOT NULL)

INSERT
INTO    @t1
VALUES  (14)
INSERT
INTO    @t1
VALUES  (44)

INSERT
INTO    @t2
VALUES  (1, 14)
INSERT
INTO    @t2
VALUES  (2, 14)
INSERT
INTO    @t2
VALUES  (1, 44)
INSERT
INTO    @t2
VALUES  (2, 44)
INSERT
INTO    @t2
VALUES  (3, 44)

INSERT
INTO    @t3
VALUES  (1)
INSERT
INTO    @t3
VALUES  (2)
INSERT
INTO    @t3
VALUES  (3)

SELECT  t1.id, t3.id
FROM    @t1 t1
CROSS JOIN
        @t3 t3
WHERE   NOT EXISTS
        (
        SELECT  NULL
        FROM    @t2 t2
        WHERE   t2.t1id = t1.id
                AND t2.t3id = t3.id
        )

Answer 3

采用以下方法解决了此问题：

WITH Nums
AS
(
    SELECT 
        1 AS Number

    UNION ALL

    SELECT 
        Number + 1
    FROM
        Nums
    WHERE 
        Number < 99 --- Max number for Transactions it will count up to
), AccountLog (Account, TransNumber, NextTransNumber)
AS
(  
    SELECT   --- Let's Generate some Sample Data
    Account,  --Pretend an Account with Transactions
    TransNumber,  --- Transaction Numbers which should be in sequence
    LEAD(TransNumber,1,0) OVER (PARTITION BY Account ORDER BY TransNumber) NextCheckNumber
    FROM (VALUES(1,2),
    (100,1),---Pretend first column is the Account and then the Transaction Number (Which was Meant to be in Sequence)
    (100,3),---As you can see we're missing numbers in sequence (1,3,7 and not 1,2,3,4,5,6,7)
    (100,7),
    (100,10),
    (200,1),
    (200,3),
    (200,11),
    (200,15)) a(Account,TransNumber)
),
MissingTrans (Account,TransNumber,TransDifference)
AS(
    SELECT 
    Account,
    TransNumber,
    NextTransNumber-TransNumber as TransDifference
    FROM AccountLog
    WHERE 
    NextTransNumber<>0
    AND
    NextTransNumber-TransNumber<>1
)
SELECT 
Account,
TransNumber+al.Number AS MissingTransNumber
FROM MissingTrans mt
CROSS JOIN Nums al
WHERE 
al.Number<mt.TransDifference
AND
mt.TransNumber+al.Number>1

如何在sql中获取缺失值？

3 个答案: