如何在SQL中的组中按顺序查找缺失值？

我有ID的表格和定位如何在SQL中的组中按顺序查找缺失值？

CREATE TABLE #MissingSequence (ID INT NOT NULL, Position INT NOT NULL) 
INSERT INTO #MissingSequence (ID,Position) 
SELECT 36,1 
UNION ALL SELECT 36,2 
UNION ALL SELECT 36,3 
UNION ALL SELECT 36,4 
UNION ALL SELECT 36,5 
UNION ALL SELECT 36,6 
UNION ALL SELECT 44,1 
UNION ALL SELECT 44,3 
UNION ALL SELECT 44,4 
UNION ALL SELECT 44,5 
UNION ALL SELECT 44,6

我试图找出是，如果有是ID位置序列在这种情况下，任何突破44.1和44.3之间

突破

我已经成功地一起解析：

SELECT l.ID 
    ,Start_Position = MIN(l.Position) + 1 
    ,Stop_Position = MIN(fr.Position) - 1 
FROM #MissingSequence l 
LEFT JOIN #MissingSequence r 
    ON l.Position = r.Position - 1 
LEFT JOIN #MissingSequence fr 
    ON l.Position < fr.Position 
WHERE r.Position IS NULL 
    AND fr.Position IS NOT NULL 
GROUP BY l.ID

，但如果有多个ID值，这是行不通的。如果只有一个ID 44存在，它确实有效。

想法，意见，建议？

谢谢！

来源

2009-04-07 Christopher Klein

你喜欢什么输出查看？有最大允许位置值吗？ – tpdi 2009-04-07 20:19:58

没有职位的最大数目...我正在处理的全表包含大约12k ID记录，职位从3到x – 2009-04-07 20:30:38

@Christopher，我的解决方案有什么问题吗？ – 2009-04-07 20:34:47

左自联接是一个很好的本能，但我不认为聚集体削减它，当然你需要在自连接中包含匹配-ID子句。

下面是使用（ANSI标准）版的空左加盟的想法，选择顶行和底行和检查两者其实没什么：

SELECT 
    above.ID AS ID, below.Position+1 AS Start_Position, above.Position-1 AS End_Position 
FROM MissingSequence AS above 
JOIN MissingSequence AS below 
    ON below.ID=above.ID AND below.Position<above.Position-1 
LEFT JOIN MissingSequence AS inbetween 
    ON inbetween.ID=below.ID AND inbetween.Position BETWEEN below.Position+1 AND above.Position-1 
WHERE inbetween.ID IS NULL; 

+----+----------------+--------------+ 
| ID | Start_Position | End_Position | 
+----+----------------+--------------+ 
| 44 |    2 |   2 | 
+----+----------------+--------------+

来源

2009-04-07 20:31:46 bobince

这个查询找到了简单的单词，希望有用;如果你是在SQL 2005，您可以使用一个CTE

SELECT ID, Position + 1 
FROM #MissingSequence t1 
WHERE (Position + 1) NOT IN (SELECT Position FROM #MissingSequence t2 WHERE t1.ID = t2.ID) 
AND Position <> (SELECT MAX(Position) FROM #MissingSequence t2 WHERE t1.ID = t2.ID)

来源

2009-04-07 20:19:00

create database testing 
use testing; 
create table sequence (
    id int not null primary key 
); 

insert into sequence(id) values 
    (1), (2), (3), (4), (6), (7), (8), (9), 
    (10), (15), (16), (17), (18), (19), (20); 

select * from sequence 

Create PROCEDURE test_proce(@mode varchar(50)) 
AS 
BEGIN 
    declare @se int; 
    set @se=0; 
    set @se=(
     select top 1 t.id + 1 
     from sequence t 
     left join sequence x on x.id = t.id + 1 
     where x.id is null 
     order by t.id 
    ); 
    select * from sequence where id<@se; 
END 

exec test_proce 'mode'

来源

2014-02-20 08:43:49 user1900387

如何在SQL中的组中按顺序查找缺失值？

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