分组的运行数据

Question

SQL专家，

是否有一个高效率的方式组运行的数据一起使用SQL?
或是它会更有效地处理数据编码。

例如，如果我有以下数据：

ID|Name
01|Harry Johns
02|Adam Taylor
03|John Smith
04|John Smith
05|Bill Manning
06|John Smith

我需要显示：

Harry Johns
Adam Taylor
John Smith (2)
Bill Manning
John Smith

@Matt：对不起我有麻烦的格式化数据使用嵌入式html表它的工作在预览，但没有在最后的显示。

Answer 1

试试这个：

select n.name, 
    (select count(*) 
     from myTable n1
     where n1.name = n.name and n1.id >= n.id and (n1.id <=
        (
        select isnull(min(nn.id), (select max(id) + 1 from myTable))
        from myTable nn
        where nn.id > n.id and nn.name <> n.name
        )
     ))
from myTable n
where not exists (
   select 1
   from myTable n3
   where n3.name = n.name and n3.id < n.id and n3.id > (
            select isnull(max(n4.id), (select min(id) - 1 from myTable))
            from myTable n4
            where n4.id < n.id and n4.name <> n.name
            )
)

我认为这会做你想要什么。位的一个暂且虽然。

唷！之后的几个编辑我认为我们所有的边缘情况。

Answer 2

我讨厌游标与激情...但这里有一个狡猾的光标。

Declare @NewName Varchar(50)
Declare @OldName Varchar(50)
Declare @CountNum int
Set @CountNum = 0

DECLARE nameCursor CURSOR FOR 
SELECT Name
FROM NameTest
OPEN nameCursor

FETCH NEXT FROM nameCursor INTO @NewName

  WHILE @@FETCH_STATUS = 0 

    BEGIN

      if @OldName <> @NewName
      BEGIN
         Print @OldName + ' (' + Cast(@CountNum  as Varchar(50)) + ')'
         Set @CountNum = 0
      END
      SELECT @OldName = @NewName
      FETCH NEXT FROM nameCursor INTO @NewName
      Set @CountNum = @CountNum + 1

    END
Print @OldName + ' (' + Cast(@CountNum  as Varchar(50)) + ')'

CLOSE nameCursor
DEALLOCATE nameCursor

Answer 3

我的解决方案只是踢(这是一个有趣的锻炼)，没有游标，没有迭代，但我确实有一个辅助领域

-- Setup test table
DECLARE @names TABLE    (
                        id      INT                 IDENTITY(1,1),
                        name    NVARCHAR(25)        NOT NULL,
                        grp     UNIQUEIDENTIFIER    NULL
                        )

INSERT @names (name)
SELECT 'Harry Johns'    UNION ALL 
SELECT 'Adam Taylor'    UNION ALL
SELECT 'John Smith'     UNION ALL
SELECT 'John Smith'     UNION ALL
SELECT 'Bill Manning'   UNION ALL
SELECT 'Bill Manning'   UNION ALL
SELECT 'Bill Manning'   UNION ALL
SELECT 'John Smith'     UNION ALL
SELECT 'Bill Manning'   

-- Set the first id's group to a newid()
UPDATE      n
SET         grp = newid()
FROM        @names n
WHERE       n.id = (SELECT MIN(id) FROM @names)

-- Set the group to a newid() if the name does not equal the previous
UPDATE      n
SET         grp = newid()
FROM        @names n
INNER JOIN  @names b
        ON  (n.ID - 1) = b.ID
        AND ISNULL(b.Name, '') <> n.Name

-- Set groups that are null to the previous group
-- Keep on doing this until all groups have been set
WHILE (EXISTS(SELECT 1 FROM @names WHERE grp IS NULL))
BEGIN
    UPDATE      n
    SET         grp = b.grp
    FROM        @names n
    INNER JOIN  @names b
            ON  (n.ID - 1) = b.ID
            AND n.grp IS NULL
END

-- Final output
SELECT      MIN(id)     AS id_start,
            MAX(id)     AS id_end,
            name,
            count(1)    AS consecutive
FROM        @names
GROUP BY    grp, 
            name
ORDER BY    id_start

/*
Results:

id_start    id_end  name            consecutive
1           1       Harry Johns     1
2           2       Adam Taylor     1
3           4       John Smith      2
5           7       Bill Manning    3
8           8       John Smith      1
9           9       Bill Manning    1
*/

Answer 4

好吧，这样的：

select Name, count(Id)
from MyTable
group by Name

会给你这个:

Harry Johns, 1
Adam Taylor, 1
John Smith, 2
Bill Manning, 1

这(MS SQL法):

select Name +
    case when ( count(Id) > 1 ) 
         then ' ('+cast(count(Id) as varchar)+')' 
         else ''
    end
from MyTable
group by Name

会给你这个:

Harry Johns
Adam Taylor
John Smith (2)
Bill Manning

你实际上想要其他的约翰*史密斯上结束你的成果？

编辑：哦，我看看，你想连续运行进行分组。在这种情况下，我想说你需要一个标或要做的是在你的程序编码。

Answer 5

这个怎么样：

declare @tmp table (Id int, Nm varchar(50));

insert @tmp select 1, 'Harry Johns';
insert @tmp select 2, 'Adam Taylor';
insert @tmp select 3, 'John Smith';
insert @tmp select 4, 'John Smith';
insert @tmp select 5, 'Bill Manning';
insert @tmp select 6, 'John Smith';

select * from @tmp order by Id;

select Nm, count(1) from 
(
select Id, Nm, 
    case when exists (
        select 1 from @tmp t2 
        where t2.Nm=t1.Nm 
        and (t2.Id = t1.Id + 1 or t2.Id = t1.Id - 1)) 
        then 1 else 0 end as Run
from @tmp t1
) truns group by Nm, Run

[编辑]，可以缩短一点

select Nm, count(1) from (select Id, Nm, case when exists (
        select 1 from @tmp t2 where t2.Nm=t1.Nm 
        and abs(t2.Id-t1.Id)=1) then 1 else 0 end as Run
from @tmp t1) t group by Nm, Run

Answer 6

对于这种特殊情况下，所有你需要做的是集团的名字，并要求为计数，是这样的：

select Name, count(*)
from MyTable
group by Name

这会让你计数为每一个名字作为第二栏中。

你可以把它作为一个列连接起来是这样的：

select Name + ' (' + cast(count(*) as varchar) + ')'
from MyTable
group by Name