Find the nearest date of one column of a table from another table

I have two tables Expense_Addl and ExchangeRates
These are the scripts
CREATE TABLE Expense_Addl (
FileId int,
HostAmt money,
HostCurrencyCd char(4),
LockDt smalldatetime
)
INSERT INTO Expense_addl values (1001, 500, 'USD', '2006-06-15')
INSERT INTO Expense_addl values (1001, 500, 'USD', '2006-06-19')
INSERT INTO Expense_addl values (1001, 500, 'USD', '2002-01-01')
In the above table HostCurrencycd can be any currenycode like 'USD',
'INR', YEN'
CREATE TABLE ExchangeRates
(CurrencyCd CHAR(4), ExchangeRate MONEY, ExchangeRateDate
SMALLDATETIME)
INSERT INTO ExchangeRates values ('USD', 0.45, '2006-06-21')
INSERT INTO ExchangeRates values ('USD', 0.40, '2006-06-14')
Now i have to update the HostAmt in Expense_Addl table taking
exchangerate for the hostcurrencycd from table ExchangeRates
for the nearest date like this
For e.g. HOstAmt in first row should take exchangerate as 0.40 because
lockdt 15th june is closet to 14th june
Similarly HOstAmt in second row should take exchangerate as 0.45
because lockdt 19th june is closet to 21st june
Similarly HOstAmt in third row should take exchangerate as 0.40 because
lockdt 01st jan is closet to 14th june
I am trying like below but not getting the correct results.
UPDATE EA
SET HostAmt = ROUND(CONVERT(MONEY,(ISNULL(((CONVERT(FL
OAT, EA.HostAmt))
* 100) / NULLIF(ISNULL(ER1.ExchangeRate,0),0),0))), 4)
FROM Expense_Addl EA(NOLOCK)
INNER JOIN ExchangeRates ER1(NOLOCK) ON EA.HostCurrencyCd =
ER1.CurrencyCd
INNER JOIN
(SELECT CurrencyCd, MAX(ExchangeRateDate) As ExchangeRateDate
FROM ExchangeRates ER ,Expense_Addl EA(NOLOCK) Where
ER.ExchangeRateDate <= EA.lockdt
GROUP BY ER.CurrencyCd
) T1
ON T1.ExchangeRateDate = ER1.ExchangeRateDate AND T1.CurrencyCd =
ER1.CurrencyCd
Can anyone help me with this ?
Regards,
Rajeev RajputHi Rajeev,
I don't know what you do that convert and nullif and all.
But I have substituted a query that will give you the exchange rate.
this update works. But no where clause for your Expense_addl.
I didn't try to figure out from your query :)
UPDATE Expense_Addl
SET HostAmt = ROUND(CONVERT(MONEY,(ISNULL(((CONVERT(FL
OAT,
Expense_Addl.HostAmt))
* 100) / NULLIF(ISNULL((select top 1 ExchangeRate from ExchangeRates ER1
where
ER1.CurrencyCd = Expense_Addl.HostCurrencyCD
order by abs(datediff(dd,ER1.ExchangeRateDate,LockDt)) asc),0),0),0))), 4)
Hope this helps.
--
-Omnibuzz (The SQL GC)
http://omnibuzz-sql.blogspot.com/|||Hi,
It is working but i have one issue with it.
When Lockdt is NULL i am getting this part as 1 -->>>>>
select top 1 ExchangeRate from ExchangeRates ER1
where
ER1.CurrencyCd = Expense_Addl.HostCurrencyCD
order by abs(datediff(dd,ER1.ExchangeRateDate,LockDt)) asc
rather i should get it as NULL
Could you please help ?
Omnibuzz thanks in advance :)
Omnibuzz wrote:

> Hi Rajeev,
> I don't know what you do that convert and nullif and all.
> But I have substituted a query that will give you the exchange rate.
> this update works. But no where clause for your Expense_addl.
> I didn't try to figure out from your query :)
> UPDATE Expense_Addl
> SET HostAmt = ROUND(CONVERT(MONEY,(ISNULL(((CONVERT(FL
OAT,
> Expense_Addl.HostAmt))
> * 100) / NULLIF(ISNULL((select top 1 ExchangeRate from ExchangeRates ER1
> where
> ER1.CurrencyCd = Expense_Addl.HostCurrencyCD
> order by abs(datediff(dd,ER1.ExchangeRateDate,LockDt)) asc),0),0),0))),
4)
>
> Hope this helps.
> --
> -Omnibuzz (The SQL GC)
> http://omnibuzz-sql.blogspot.com/