Consider the following database instance.

SALESPERSON

Sname Sid Region Quota(Doller)
Frances  25 TX 100
Bob 31 CA 150
Frances 74 MA 200
Mary 89 FL 250

 

PRODUCTS

Pname Pid Pprice(Doller)
dishs 131 100
pes 152 700
macs 831 800
printers 255 120
paper 221 5

 

CUSTOMERS

Cname Cid Region
Bob 1 TX
Harry 2 TX
Lin 3 MA
Martha 4 FL
Lin 5 FL
Leyla 6 CA

 

ORDERS

Cid Pid Quantity
1 152 1
2 152 1
3 831 1
4 131 1
5 255 1
6 831 1

What will be the number of rows in the result of the following query on the instance?

\Pi _{Sname}((SALESPERSON \Join CUSTOMER)\Join (\sigma _{Pname='macs'}(PRODUCTS \Join ORDERS)))

Answer hidden