Figuer:
-What programmer's or user's decision typically will affect the performance of the query?
A) Placing the condition "PICKUP = 'ERIE' OR PICKUP = 'CARY'" before the condition "CUSTOMER.CID = RENTALS.CID" in the query.
B) Placing the condition "PICKUP = 'ERIE' OR PICKUP = 'CARY'" after the condition "CUSTOMER.CID = RENTALS.CID" and before the condition "RENTALS.MAKE = RENTCOST.MAKE" in the query.
C) Selecting the attributes CID in CUSTOMERS and CID in RENTALS as indexes on the tables.
D) None of the above

Question

Figuer: 
-What programmer's or user's decision typically will affect the performance of the query?
A) Placing the condition "PICKUP = 'ERIE' OR PICKUP = 'CARY'" before the condition "CUSTOMER.CID = RENTALS.CID" in the query. 
B) Placing the condition "PICKUP = 'ERIE' OR PICKUP = 'CARY'" after the condition "CUSTOMER.CID = RENTALS.CID" and before the condition "RENTALS.MAKE = RENTCOST.MAKE" in the query. 
C) Selecting the attributes CID in CUSTOMERS and CID in RENTALS as indexes on the tables. 
D) None of the above

Quizplus · Accepted Answer

Selecting attributes as indexes (choice C) can significantly improve query performance by reducing the amount of data the database system needs to scan to fulfill a query. Indexes provide a faster access path to data rows in tables based on the indexed columns. Choices A and B, which involve the order of conditions in a query, typically do not affect performance in modern database systems because query optimizers internally rearrange conditions for optimal execution.

Figuer: -What Programmer's or User's Decision Typically Will Affect the Performance