Link to home
Start Free TrialLog in
Avatar of rocky_lotus_newbie
rocky_lotus_newbieFlag for India

asked on

SQL Server Query Help

Hi Experts,

I have a customersales table and I am using the below query to find out the maximum salesid for each customer.

SELECT MAX(SaleID),CustomerID
FROM CustomerSales
GROUP BY CustomerID

It takes a very high cpu and time. CustomerSales table has 4 million records.

Can you please guide me if there a better and efficient way to write this query.

Thanks,
ASKER CERTIFIED SOLUTION
Avatar of Ephraim Wangoya
Ephraim Wangoya
Flag of United States of America image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
SOLUTION
Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
SOLUTION
Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
SOLUTION
Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Avatar of rocky_lotus_newbie

ASKER

Thanks for the Inputs, I will try these indexes and see if it performs better.
Shiva - you want to create 3 indexes ALL on the same [first] column on a SINGLE table??
Avatar of spmamidi
spmamidi


Yes - There is a typo for Creating third Index.

Here is the correct version - CREATE  INDEX Sales_OrderId_Index3 ON CustomerSales(SaleID) INCLUDE (CustomerID);

Shiva Mamidi