Find The Last Record By Date In A Sub Group Of Records.

Looking to see if thier is a better way to find the last record entered in a group of records.

What I'm doing now is finding the max for the secound column and then doing a sub query to find the max of the third column having the second columns equal.

Table example using simplied data.






PolId

CoveragId

EffDate

Status

Limit1


2

1

9/7/2007

a

10000


2

2

9/7/2007

a

150000


2

2

10/1/2007

a

200000


3

1

9/7/2007

a

10000

The parent program addes a row every time the data is changed. To make things worst; the records arn't always in sqenal order like the above table and some time edits the row instead.

The current query returns a single value. from a single table.

Current code used in the select protion on a larger query. bpi = basicpolicyInformation.

( Select c1.limit1
From AFW_Coverage as c1
Where c1.PolId=bpi.PolId
and c1.CoverageId = (select max(CoverageId) as CoverageId
From AFW_Coverage as c
where c.PolId = c1.PolId
and c.CoverageCode = 'Dwelling'
and status <> 'D'
)
and c1.effDate = (select max(Effdate) as Effdate
From AFW_Coverage as c
where c.PolId = c1.PolId
and c.CoverageID = c1.CoverageId
)


Explain the current code. It uses the two sub queries to find the correct record ID that has the data needed.