DBMS - Concurrency Control

In order to maintain transactional integrity and database consistency, what technology does a DBMS deploy?

• Triggers

• Pointers

• Locks

• Cursors

A lock that allows concurrent transactions to access different rows of the same table is known as a

• Database-level lock

• Table-level lock

• Page-level lock

• Row-level lock

Which of the following are introduced to reduce the overheads caused by the log-based recovery?

• Checkpoints

• Indices

• Deadlocks

• Locks

Which of the following protocols ensures conflict serializability and safety from deadlocks?

• Two-phase locking protocol

• Time-stamp ordering protocol

• Graph based protocol

• None of the mentioned

Which of the following is the block that is not permitted to be written back to the disk?

• Dead code

• Read only

• Pinned

• Zapped

If transaction Ti gets an explicit lock on the file Fc in exclusive mode, then it has an ­­­­­­__________ on all the records belonging to that file.

• Explicit lock in exclusive mode

• Implicit lock in shared mode

• Explicit lock in shared mode

• Implicit lock in exclusive mode

Which refers to a property of computer to run several operation simultaneously and possible as computers await response of each other

• Concurrency

• Deadlock

• Backup

• Recovery

All lock information is managed by a __________ which is responsible for assigning and policing the locks used by the transactions.

• Scheduler

• DBMS

• Lock manager

• Locking agent

The ____ lock allows concurrent transactions to access the same row as long as they require the use of different fields within that row.

• Table-level

• Page-level

• Row-level

• Field-level

Which of the following is a procedure for acquiring the necessary locks for a transaction where all necessary locks are acquired before any are released?

• Record controller

• Exclusive lock

• Authorization rule

• Two phase lock