Database-Management-System
October 4, 2023Database-Management-System
October 4, 2023UGC-NET DEC-2019 Part-2
| Question 20 |
Which of the component module of DBMS does rearrangement and possible ordering of operations, eliminate redundancy in query and use efficient algorithms and indexes during the execution of a query?
| query compiler | |
| query optimizer | |
| Stored data manager | |
| Database processor |
Question 20 Explanation:
The query optimizer (called simply the optimizer) is built-in database software that determines the most efficient method for a SQL statement to access requested data. The optimizer choose the plan with the lowest cost among all considered candidate plans(the cost computation accounts for factors of query execution such as I/O, CPU, and communication).
It rearrange and does the possible ordering of operations, eliminate redundancy in query and use efficient algorithms and indexes during the execution of a query
It rearrange and does the possible ordering of operations, eliminate redundancy in query and use efficient algorithms and indexes during the execution of a query
Correct Answer: B
Question 20 Explanation:
The query optimizer (called simply the optimizer) is built-in database software that determines the most efficient method for a SQL statement to access requested data. The optimizer choose the plan with the lowest cost among all considered candidate plans(the cost computation accounts for factors of query execution such as I/O, CPU, and communication).
It rearrange and does the possible ordering of operations, eliminate redundancy in query and use efficient algorithms and indexes during the execution of a query
It rearrange and does the possible ordering of operations, eliminate redundancy in query and use efficient algorithms and indexes during the execution of a query