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DBMS → DDL Commands 3

A lock that prevents the use of any tables in the database from one transaction while another transaction is being processed is called a
database-level lock
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The recovery scheme must also provide
high availability
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The                        policy, allows the system to write modified blocks to disk even if the transactions that made those modifications have not all committed.
steal
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DBMS → DML Commands 3

A condition that occurs when two transactions wait for each other to unlock data is known as a(n)
deadlock
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Which one of the following is a failure to a system
transaction failure
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The                                      contains a list of blocks that have been updated in the database buffer.
dirty block
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DBMS → Joins 3

The extent of the database resource that is included with each lock is called the level of
granularity
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The system has entered an undesirable state (for example, deadlock), as a result of which a transaction cannot continue with its normal execution. This is
logical error
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The silicon chips used for data processing are called
prom chips
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DBMS → Views 3

DBMS periodically suspends all processing and synchronizes its files and journals through the use of
checkpoint facility
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The transaction can no longer continue with its normal execution because of some internal condition, such as bad input, data not found, overflow, or resource limit exceeded. This is
logical error
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Which of the following is used for manufacturing chips?
semiconductor
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DBMS → Indexes 2

Snapshot isolation is used to give
transaction a snapshot of the database and database a snapshot of committed values in the transaction
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The assumption that hardware errors and bugs in the software bring the system to a halt, but do not corrupt the nonvolatile storage contents, is known as the
fail-stop assumption
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DBMS → Transactions 2

Lost update problem is
second update overwrites the first
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The database is partitioned into fixed- length storage units called
blocks
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DBMS → Concurrency Control 2

Each of a pair of transactions has read data that is written by the other, but there is no data written by both transactions, is referred to as
none of the mentioned
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The log is a sequence of                     recording all the update activities in the database.
log records
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DBMS → Deadlock 2

Which statements are correct regarding indexes?
all of the mentioned
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In the                        scheme, a transaction that wants to update the database first creates a complete copy of the database.
shadow copy
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DBMS → Database Security 2

A non-correlated subquery can be defined as                 
a set of one or more sequential queries in which generally the result of the inner query is used as the search value in the outer query
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The                          scheme uses a page table containing pointers to all pages; the page table itself and all updated pages are copied to a new location.
shadow paging
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DBMS → PL/SQL 2

Which statement is true regarding synonyms?
a public synonym and a private synonym can exist with the same name for the same table
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If a transaction does not modify the database until it has committed, it is said to use the                        technique.
deferred-modification
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DBMS → Introduction to DBMS 2

The method of access that uses key transformation is called as
hash
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                         using a log record sets the data item specified in the log record to the old value.
undo
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DBMS → Database Architecture 2

Why do we need concurrency control on B+ trees ?
to maintain accuracy of index
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In the                      phase, the system replays updates of all transactions by scanning the log forward from the last checkpoint.
redo
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DBMS → Data Models 2

How many techniques are available to control concurrency on B+ trees?
none of the mentioned
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The actions which are played in the order while recording it is called                               history.
repeating
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DBMS → ER Model 2

In crabbing protocol locking
goes down the tree and back up
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A special redo-only log record < Ti, Xj, V1> is written to the log, where V1 is the value being restored to data item Xj during the rollback. These log records are sometimes called
compensation log records
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DBMS → Relational Model 2

The deadlock can be handled by
restarting the search after releasing the lock
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In order to reduce the overhead in retrieving the records from the storage space we use
log buffer
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DBMS → Normalization 2

In crabbing protocol, the lock obtained on the root node is in                    mode.
shared
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Writing the buffered log to                      is sometimes referred to as a log force.
disk
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DBMS → Functional Dependency 2

If needed to split a node or coalesce it with its siblings, or redistribute key values between siblings, the crabbing protocol locks the parent of the node in                           mode.
exclusive
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The                                policy, allows a transaction to commit even if it has modified some blocks that have not yet been written back to disk.
no-force
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DBMS → SQL Basics 2

Instead of locking index leaf nodes in a two-phase manner, some index concurrency- control schemes use                        on individual key values, allowing other key values to be inserted or deleted from the same leaf.
key-value locking
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                             policy allows multiple updates to accumulate on a block before it is output to stable storage, which can reduce the number of output operations greatly for frequently updated blocks.
no-force
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