求一sql语句

[vfan2010]

现在有以下的table
ProjectID 　　　StartDate EndDate　 　　　Workers
1 2006.2 2006.3 321
1 2006.3 2006.4 12
1 2006.4 2006.5 45

现在用户以ProjectID=1和StartDate为2006.2，EndDate为2006.5要得到以下的结果,也就是列是动态变化的，如何写sql语句。

ProjectID　　　　　　　2006.2　 　　 2006.3 　　 2006.4
1 321 12 45

[cpp2017]

交叉表. 交叉数据报表 有时候需要旋转结果以便在水平方向显示列，而在垂直方向显示行。这就是所谓的创建 PivotTable?、创建交叉数据报表或旋转数据。 假定有一个表 Pivot，其中每季度占一行。对 Pivot 的 SELECT 操作在垂直方向上列出这些季度： Year Quarter Amount ---- ------- ------ 1990 1 1.1 1990 2 1.2 1990 3 1.3 1990 4 1.4 1991 1 2.1 1991 2 2.2 1991 3 2.3 1991 4 2.4 生成报表的表必须是这样的，其中每年占一行，每个季度的数值显示在一个单独的列中，如： Year Q1 Q2 Q3 Q4 1990 1.1 1.2 1.3 1.4 1991 2.1 2.2 2.3 2.4 下面的语句用于创建 Pivot 表并在其中填入第一个表中的数据： USE Northwind GO CREATE TABLE Pivot ( Year SMALLINT, Quarter TINYINT, Amount DECIMAL(2,1) ) GO INSERT INTO Pivot VALUES (1990, 1, 1.1) INSERT INTO Pivot VALUES (1990, 2, 1.2) INSERT INTO Pivot VALUES (1990, 3, 1.3) INSERT INTO Pivot VALUES (1990, 4, 1.4) INSERT INTO Pivot VALUES (1991, 1, 2.1) INSERT INTO Pivot VALUES (1991, 2, 2.2) INSERT INTO Pivot VALUES (1991, 3, 2.3) INSERT INTO Pivot VALUES (1991, 4, 2.4) GO 下面是用于创建旋转结果的 SELECT 语句： SELECT Year, SUM(CASE Quarter WHEN 1 THEN Amount ELSE 0 END) AS Q1, SUM(CASE Quarter WHEN 2 THEN Amount ELSE 0 END) AS Q2, SUM(CASE Quarter WHEN 3 THEN Amount ELSE 0 END) AS Q3, SUM(CASE Quarter WHEN 4 THEN Amount ELSE 0 END) AS Q4 FROM Northwind.dbo.Pivot GROUP BY Year GO 该 SELECT 语句还处理其中每个季度占多行的表。GROUP BY 语句将 Pivot 中一年的所有行合并成一行输出。当执行分组操作时，SUM 聚合中的 CASE 函数的应用方式是这样的：将每季度的 Amount 值添加到结果集的适当列中，在其它季度的结果集列中添加 0。 如果该 SELECT 语句的结果用作电子表格的输入，那么电子表格将很容易计算每年的合计。当从应用程序使用 SELECT 时，可能更易于增强 SELECT 语句来计算每年的合计。例如： SELECT P1.*, (P1.Q1 + P1.Q2 + P1.Q3 + P1.Q4) AS YearTotal FROM (SELECT Year, SUM(CASE P.Quarter WHEN 1 THEN P.Amount ELSE 0 END) AS Q1, SUM(CASE P.Quarter WHEN 2 THEN P.Amount ELSE 0 END) AS Q2, SUM(CASE P.Quarter WHEN 3 THEN P.Amount ELSE 0 END) AS Q3, SUM(CASE P.Quarter WHEN 4 THEN P.Amount ELSE 0 END) AS Q4 FROM Pivot AS P GROUP BY P.Year) AS P1 GO 带有 CUBE 的 GROUP BY 和带有 ROLLUP 的 GROUP BY 都计算与本例显示相同的信息种类，但格式稍有不同。

[vfan2010]

加了一个星？不错啊

[stone3_hl]

好强呀，顶一下

[dinoLgrace]

算了，木白兄来了问题就解决了，帮顶@！

[smile9961]

存储过程：
create proc dbo.workers_by_month
(
@projectId int
)
as
begin
declare @sql varchar(8000)
set @sql = 'select projectId'

select@sql = @sql +', sum(case startdate when ''' + startdate + ''' then workers else 0 end) as ''' + startdate + ''''
from (select distinct startdate from 表 where projectId = @projectId) x

set @sql = @sql + ' from 表 where projectId = ' + @projectId ' + group by projectId '

exec (@sql)
end
go

调用：
exec workers_by_month 1

[confei]

declare @tptable table(yr nvarchar(4),amt nvarchar(1))

insert into @tptable(yr,amt)values('2007','1')


insert into @tptable(yr,amt)values('2007','1')

insert into @tptable(yr,amt)values('2007','3')

insert into @tptable(yr,amt)values('2007','4')

insert into @tptable(yr,amt)values('2008','2')

insert into @tptable(yr,amt)values('2008','3')

insert into @tptable(yr,amt)values('2008','4')

insert into @tptable(yr,amt)values('2009','1')

insert into @tptable(yr,amt)values('2009','2')

insert into @tptable(yr,amt)values('2009','3')

insert into @tptable(yr,amt)values('2009','4')

--select * from @tptable

select distinct yr
,sum(case amt when '1' then 1 else 0 end) as a1
,sum(case amt when '2' then 2 else 0 end) as a2
,sum(case amt when '3' then 3 else 0 end) as a3
,sum(case amt when '4' then 4 else 0 end) as a4 from @tptable
group by yr

[confei]

学习了 哈哈

[smile9961]

create table dbo.test
(
projectId int,
startdate nvarchar(10),
enddate nvarchar(10),
workers int
)

insert into test
select 1, 2006.02, 2006.03, 321 union all
select 1, 2006.03, 2006.04, 12 union all
select 1, 2006.04, 2006.05, 45

alter proc dbo.workers_by_month
(
@projectId int
)
as
begin
declare @sql varchar(8000)
set @sql = 'select projectId'

select @sql = @sql +', sum(case startdate when ''' + startdate + ''' then workers else 0 end) as [' + startdate + '] '
from (select distinct startdate from test where projectId = @projectId) x

set @sql = @sql + ' from test where projectId = ' + convert(varchar(20), @projectId) + ' group by projectId '

exec (@sql)
end
go

exec workers_by_month 1

drop proc workers_by_month
drop table test

[smile9961]

之所以要将2006.2转变为2006.02，是因为如果按文本排序，2006.10将会排在2006.2之后.这个是最后的：

create table dbo.test
(
projectId int,
startdate nvarchar(10),
enddate nvarchar(10),
workers int
)

insert into test
select 1, '2006.02', '2006.03', 321 union all
select 1, '2006.03', '2006.04', 12 union all
select 1, '2006.10', '2006.11', 560 union all
select 1, '2006.04', '2006.05', 45

alter proc dbo.workers_by_month
(
@projectId int
)
as
begin
declare @sql varchar(8000)
set @sql = 'select projectId'

select @sql = @sql +', sum(case startdate when ''' + startdate + ''' then workers else 0 end) as [' + startdate + '] '
from (select distinct startdate from test where projectId = @projectId) x

set @sql = @sql + ' from test where projectId = ' + convert(varchar(20), @projectId) + ' group by projectId '

exec (@sql)
end
go

exec workers_by_month 1

drop proc workers_by_month
drop table test

[amandag]

--测试数据
create table Test
(
projectID int,
startdate datetime,
enddate datetime,
workers int
)

insert into Test
select 1,'2006-2-1','2006-3-1',321
union all select 1,'2006-3-1','2006-4-1',12
union all select 1,'2006-4-1','2006-5-1',45
union all select 2,'2006-4-1','2006-6-1',100

--创建存储过程
create proc myproc
(
@projectID int,
@startdate as datetime,
@enddate as datetime
)
as
begin
declare @S as varchar(1000)
Select @S = 'SELECT ProjectID '
while @startdate < @enddate
begin
Select @S = @S + ',sum(case convert(varchar(10),startdate) when ''' + convert(varchar(10),@startdate) + ''' then workers else 0 end)' + ' as [' + convert(varchar(4), year(@startdate)) + '.' + convert(varchar(2),month(@startdate)) + ']'
set @startdate = DATEADD (mm,1,@startdate)
end
Select @S = @S + ' From Test where projectid = ' + Convert(varchar(4), @projectid) + ' Group By projectid'
print @S
exec (@S)
end

--测试
exec myproc 1, '2006-2-1', '2006-5-1'

exec myproc 2, '2006-2-1', '2006-5-1'

[wfcfan]

强。

[smalladam]

进来学习