Evaluation of Expressions

Question 1
Marks : +2 | -2
Pass Ratio : 100%
Which of the following techniques does not exist?
Pipelined join technique
Left pipelined join technique
Right pipelined join technique
None of the mentioned
Explanation:
Pipelined join technique, both left and right are evaluation techniques that can be used to organize data.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
Which of the following functions does an iterator not provide
Open()
Next()
Close()
Wait()
Explanation:
The iterator does not provide the wait() function but it provides open(), next() and close() operations.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
If the system makes repeated requests for tuples from the operation at the top of the table, it is called as _________
Demand driven pipeline
Producer driven pipeline
Query driven pipeline
None of the mentioned
Explanation:
If the system makes repeated requests for tuples from the operation at the top of the table, it is called as demand driven pipeline. Each time an operation receives a request for tuples, it computes the next tuple or tuples to be returned and then returns that tuple.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
State true or false: Sorting is an inherently blocking operation
True
False
Explanation:
Sorting is an inherently blocking operation i.e. output is not given until all the tuples from their input are examined
Question 5
Marks : +2 | -2
Pass Ratio : 100%
The result of each intermediate operation are created and then are used for valuation of the next level operations, this evaluation is called as ________
Chain evaluation
Pipeline evaluation
Materialized evaluation
Demand driven evaluation
Explanation:
The result of each intermediate operation are created and then are used foe valuation of the next level operations, this evaluation is called as Materialized evaluation. This is not space effective as we need to construct the temporary relations which must be written to a disk.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
If the results of one operation are passed on to the other, it is called as ________
Chain
Pipeline
Materialized
Tree
Explanation:
If the results of one operation are passed on to the other, it is called as Pipelined. This can be used to evaluate several expressions simultaneously.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
If the operations do not wait to produce tuples, then it is called as _________
Demand driven pipeline
Producer driven pipeline
Query driven pipeline
None of the mentioned
Explanation:
If the operations do not wait to produce tuples, then it is called as producer driven pipeline. IT does not wait to produce tuples but it produces tuples eagerly.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
State true or false: Join is an inherently blocking operation
True
False
Explanation:
Join is not an inherently blocking algorithm. This is because all the tuples need not be examined to execute the join operation.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
The usage of two buffers, with one continuing execution of the algorithm while the other is written is called as __________
Double execution
Multi tasking
Double buffering
Double algorithm
Explanation:
The usage of two buffers, with one continuing execution of the algorithm while the other is written is called as Double buffering. This makes the algorithm quicker by performing CPU operations simultaneously with the I/O operations.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
State true or false: Hybrid hash join is partially pipelined on the probe relation
True
False
Explanation:
Hybrid hash join is partially pipelined on the probe relation since it can output tuples from the first partition as tuples are received for the probe relation.