I agree with Rune Bivrin's comment. There are two correct answers, as far as I can tell.

--> Steve Jones:  If we are incorrect, please provide test data that clearly demonstrates...

• This reply was modified 3 years, 9 months ago by  Tom Wickerath.
• This reply was modified 3 years, 9 months ago by  Tom Wickerath.

@sizal0234 (SSCrazy):

Need little help. What version of AdventureWorks sample DB is being used in "Stairway to SQL Server Indexes"

I see some difference while running sample queries in my...

I'm curious about one more thing....

In Level 2 and most of Level 3, the number of logical reads I observed matches very close with the values given by the author....

<Quote>

After creating the clustered index shown above, the resulting table / clustered index would look like this:

SalesOrderID SalesOrderDetailID ProductID   OrderQty UnitPrice

26 rows of data shown

As you look at the sample...

• This reply was modified 4 years, 10 months ago by  Tom Wickerath.

Additional information provided by my friend, Microsoft Access MVP Ben Clothier, via a private email (after I thanked him):

"You're welcome! To be honest it did puzzle me for a bit;...

• This reply was modified 4 years, 11 months ago by  Tom Wickerath.

Hi Jeff,

Care to provide an example INSERT query or two that demonstrates the possible surprise you mention--I assume in this case the possibility of double booking a room?

Thanks

• This reply was modified 4 years, 11 months ago by  Tom Wickerath.

A friend of mine, Microsoft Access MVP Ben Clothier, provided a fix. Change the following line of code from "less than" to "less than or equal to":

            
December 20, 2019 at 9:34 pm
            
#3709699

            
            
                                                
        

SQL Server 2017 (CU18)

I cannot get Joe Celko's example to work, as advertised!

create table Hotel
  (room_nbr integer not null,
   arrival_date date not null,
 ...