Select Min Value In An Inner Join

Hello,

I'd appreciate any help with the following problem.

I'm trying to update a table using an inner self join.

I've a list of historical records with start dates, and I need to add end dates to the records, using the start date of the next record.

The table I'm using looks like this
CREATE TABLE [dbo].[IbesEstimateHist](
[IbesEstimateHistId] [int] IDENTITY(1,1) NOT NULL,
[IbesEstimateId] [int] NULL,
[EstimateDate] [datetime] NULL,
[EstimateEndDate] [datetime] NULL CONSTRAINT [DF_IbesEstimateHist_EstimateEndDate] DEFAULT ('9999-12-31 00:00.000'),
[Value] [decimal](13, 4) NULL,
CONSTRAINT [PK_IbesEstimateHist] PRIMARY KEY CLUSTERED
(
[IbesEstimateHistId] ASC
)WITH (PAD_INDEX = OFF, IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]

and here's some example data

insert into IbesEstimateHist
([IbesEstimateId],[EstimateDate],[EstimateEndDate],[Value])
values(1,'2006-01-01','9999-12-31',100)
insert into IbesEstimateHist
([IbesEstimateId],[EstimateDate],[EstimateEndDate],[Value] )
values (1,'2006-02-01','9999-12-31',100)
insert into IbesEstimateHist
([IbesEstimateId],[EstimateDate],[EstimateEndDate],[Value])
values (1,'2006-03-01','9999-12-31',100)

These are three historical records for the same estimate, I want to set the end dates of the earlier records to the start date of the next record that was recieved.

This is the SQL that I've tried using but I can't seem to get it right

select esth1.IbesEstimateId, esth1.EstimateEndDate,min(next.estimatedate)
from IbesEstimateHist esth1
inner join
(
select esth2.EstimateDate as estimatedate, esth2.IbesEstimateId
from IbesEstimateHist esth2
) as next
on esth1.IbesEstimateId = next.IbesEstimateId
and esth1.EstimateDate < next.estimatedate
group by esth1.IbesEstimateId, esth1.EstimateEndDate

I'd be grateful for any help, thanks.




















Sean_B