Sequence - SQL Server Forums

Please start any new threads on our new site at https://forums.sqlteam.com. We've got lots of great SQL Server experts to answer whatever question you can come up with.

All Forums

General SQL Server Forums

New to SQL Server Programming

Sequence

Author

Topic

Clas
Starting Member

33 Posts

Posted - 2009-04-01 : 08:40:15

When there is an CHANGE in value, compare to previos row --> new seq number
Same value can occur in later date, so I can not group on values

Create table #temp
(
EventDate datetime,
Value int,
sequence int
)
insert into #temp values('1925-02-02' , 25 , 0)
insert into #temp values('1927-03-03' , 25 , 0)
insert into #temp values('1931-04-04' , 100 , 0)
insert into #temp values('1931-05-05' , 100 , 0)
insert into #temp values('1935-08-09' , 100 , 0)
insert into #temp values('1945-02-03' , 25 , 0)
insert into #temp values('1950-03-08' , 25 , 0)
insert into #temp values('1951-07-08' , 26 , 0)

select * from #temp

/**
Update #temp sequence , order by eventdate

RESULT:

1925-02-02 , 25 seq:1
1927-03-03 , 25 seq:1

1931-04-04 , 100 seq:2
1931-05-05 , 100 seq:2
1935-08-09 , 100 seq:2

1945-02-03 , 25 seq:3
1950-03-08 , 25 seq:3

1951-07-08 , 26 seq:4

THANKS !
**/

darkdusky
Aged Yak Warrior

591 Posts

Posted - 2009-04-01 : 09:49:44

Can you rephrase "When there is an CHANGE in value, compare to previos row --> new seq number
Same value can occur in later date, so I can not group on values"
I don't understand your meaning.

madhivanan
Premature Yak Congratulator

22864 Posts

Posted - 2009-04-01 : 09:54:16

Here is one way

declare @temp table 
(
EventDate datetime,
Value int,
sequence int
)
insert into @temp  values('1925-02-02' , 25 , 0)
insert into @temp  values('1927-03-03' , 25 , 0)
insert into @temp  values('1931-04-04' , 100 , 0)
insert into @temp  values('1931-05-05' , 100 , 0)
insert into @temp  values('1935-08-09' , 100 , 0)
insert into @temp  values('1945-02-03' , 25 , 0)
insert into @temp  values('1950-03-08' , 25 , 0)
insert into @temp  values('1951-07-08' , 26 , 0)

declare @value int,@sequence int
set @sequence=0
update @temp
set sequence=case when @value=value then @sequence else sequence end,
@sequence=case when @value=value then @sequence else @sequence+1 end,@value=value 

select * from @temp

Madhivanan

Failing to plan is Planning to fail

Subscribe to SQLTeam.com

SQLTeam.com Articles via RSS

SQLTeam.com Weblog via RSS

- Advertisement -

Resources