BITS WILP Database Design and Applications Quiz-3 2017-H1

Question 1

In Primary indexing the first record of every data block is known as___ of the block.

Select one:

head record

Key record

lead record

anchor record

Feedback

The correct answer is: anchor record

Question 2

Which of the following is not correct about indexing.

Select one:

An index built on a key attribute of  file is always sparse.

At the same time, we cannot have both  primary index and clustering index on a given file.

There can be any number of secondary indexes on  file.

Primary index is a sparse index.

Feedback

The correct answer is: An index built on a key attribute of  file is always sparse.

Question 3

In a B  tree, record pointers are found at_

Select one:

Any level.

Only at intermediate level.

Any level excepting the root level.

Only at leaf level.

Feedback

The correct answer is: Any level.

Question 4

Serializability can be implemented using_

Select one:

Transaction Model

Serial Schedules

Views

Wait-for Graphs

Locks

Feedback

The correct answer is: Locks

Question 5

Checkpointing helps in_

Select one:

Avoiding unnecessary Redo operations during recovery

Increasing consistency during recovery of the Database

Reducing deadlocks during concurrent execution of transactions

Increasing the serializability of a schedule

Preventing Deadlocks during concurrent execution of transactions

Feedback

The correct answer is: Avoiding unnecessary Redo operations during recovery

Question 6

Which of the following is correct w.r.t., Shadow paging technique?

Select one:

We always make changes to shadow page table((shadow directory) only

Once the transaction is successful, we discard the shadow page table(shadow directory)

If transaction fails, we discard the shadow page table(shadow directory)

Once the transaction is successful, we discard the current page table (current directory)

Feedback

The correct answer is: Once the transaction is successful, we discard the shadow page table(shadow directory)

Question 7

Assume that we have 3500 index blocks in  the third level of multilevel Indexing structure. If the Block size is 1024Bytes and the blocking factor for Index file is 32, then we need __ number of index blocks at 4^th level. 

Assume unspanned records organization.

Select one:

32

110

109

111

33

Feedback

The correct answer is: 110

Question 8

Assume that we have 234570 Data records, with 120 Bytes as record size. If the Block size is 1024 then we need __ number of data blocks for the. Assume unspanned records organization.

Select one:

9

1956

29322

230

Feedback

The correct answer is: 29322

Question 9

If we have 453890 data blocks and 4280 Index blocks in a Primary indexing scheme, then the number of block accesses needed to retrieve a record with given key value is_.

Select one:

11

13

12

14

15

Feedback

The correct answer is: 14

Question 10

If we have  4280 Index blocks in first level of a multilevel index.  The record size is 120 Bytes, fan-out of the multilevel index block is 34, then the number of data blocks in the file are __.

Select one:

Always less than  145486

Greater than 145486  and less than  145521

4280

145520

less than or equal to 145486

Feedback

The correct answer is: Greater than 145486  and less than  145521

Question 11

Which of the following is true in case of a B+ tree?

Select one:

The number of pointers in each internal node depends only on the block size.

For a B+ tree of P=5 (order of the B+ tree =5 ) the root node can have more than 5 pointers.

For a B+ tree of P=5 (order of the B+ tree =5 ) all leaves need not be at same level.

For a B+ tree of P=5 (order of the B+ tree =5 ) any internal node will have maximum of 4 keys.

Feedback

The correct answer is: For a B+ tree of P=5 (order of the B+ tree =5 ) any internal node will have maximum of 4 keys.

Question 12

Which of the following is true in case of Time-stamp based concurrency control protocol?

Select one:

Every data item is associated with one time-stamp.

Only shared locks are used.

Only exclusive locks are used.

Resolves deadlocks based on time-stamps.

No possibility of deadlocks.

Feedback

The correct answer is: No possibility of deadlocks.

Question 13

Which of the following is true in case of  Transaction processing and schedules model?

Select one:

A serializable schedule is always a serial schedule

In a  serializable schedule we don't see any conflicting pair of operations.

In a  serializable schedule there can be some conflicting pair of operations.

A partially committed transaction cannot be rolledback

Feedback

The correct answer is: In a  serializable schedule there can be some conflicting pair of operations.

Question 14

It is possible to have more than one clustering index on a file.

Select one:

True

False

Feedback

The correct answer is 'False'.

Question 15

A transaction can go to ‘failed’ state from partially committed state.

Select one:

True

False

Feedback

The correct answer is 'True'.