Deck 6: Database Administration

Question 1

The purpose of concurrency control is to ensure that one user's work does not inappropriately influence another user's work.

Answer 1

True

Question 2

Database security is easy to achieve since all security is handled by the DBMS,which is a single point of entry into the database.

Answer 2

False

Question 3

Generally,the more restrictive the transaction isolation level,the less the throughput of database processing.

Answer 3

True

Question 4

Only large database systems have a need for database administration.

Question 5

In comparison to reprocessing,rollforward does not involve the application programs.

Question 6

The simplest and most feasible means of recovering a database is through reprocessing.

Question 7

With optimistic locking,locks are first issued,then the transaction is processed,and then the locks are released.

Question 8

In terms of database security,a user can be assigned many roles,and a role can be assigned to many users.

Question 9

Transactions should be written to the log before they are applied to the database itself.

Question 10

The acronym DBA refers to either the office or the manager.

Question 11

All actions in an atomic transaction are completed successfully or none of the actions are completed at all.

Question 12

Lock granularity refers to whether a lock is placed by the DBMS automatically or is placed by a command from the application program.

Question 13

Concurrent processing of a database only poses problems when two or more processes attempt to use the same data.

Question 14

One advantage of optimistic locking is that the lock is obtained only after the transaction is processed.

Question 15

A dirty read is a problem with concurrent processing when a transaction rereads data it has already read and finds modifications or deletions caused by another transaction.

Question 16

Two-phase locking can be used to ensure that transactions are serializable.

Question 17

A transaction in which all steps must be completed successfully or none of them will be completed is called a durable transaction.

Question 18

One way to prevent concurrent processing problems is to lock data that are retrieved for update.

Question 19

Statement level consistency means that all statements within a transaction will access consistent rows across the lifetime of the entire transaction.

Question 20

Rollback requires the use of logs,but rollforward does not.

Question 21

Which of the following is true about a shared lock?

A)It is more restrictive than an implicit lock.
B)It allows only two transactions to update a record simultaneously.
C)It locks the item from all access.
D)It allows reads to the locked item.
E)It must use a two-phase locking scheme.

Question 22

An ACID transaction is one that is:

A)atomic.
B)consistent.
C)isolated.
D)durable.
E)All of the above

Question 23

What is the least restrictive isolation level that will prevent dirty reads?

A)Read Committed
B)Serializable
C)Read Uncommitted
D)Atomic Read
E)Repeatable Read

Question 24

What is the least restrictive isolation level that will prevent nonrepeatable reads?

A)Read Committed
B)Serializable
C)Read Uncommitted
D)Atomic Read
E)Repeatable Read

Question 25

When Microsoft Access 2013 uses user-level security with an Access 2003 file,the database is stored in a(n)*.accdb file.

Question 26

What concurrent processing problem occurs when a transaction rereads data and finds new rows that were inserted by a different transaction since the prior read?

A)Nonrepeatable reads
B)Phantom reads
C)Dirty reads
D)Serialized reads
E)Unlocked reads

Question 27

Microsoft Access 2013 uses a user-level security system.

Question 28

Ensuring that each SQL statement independently processes consistent rows is known as:

A)transaction level consistency.
B)independent consistency.
C)statement level consistency.
D)process level consistency.
E)serializable consistency.

Question 29

Microsoft Access 2013 databases can be secured using trusted locations for database storage.

Question 30

What is the least restrictive isolation level that will prevent phantom read problems?

A)Read Committed
B)Serializable
C)Read Uncommitted
D)Atomic Read
E)Repeatable Read

Question 31

Which type of lock assumes that no conflicts will occur?

A)Optimistic locks
B)Granular locks
C)Explicit locks
D)Shared locks
E)Open locks

Question 32

Which of the following is not a means of processing databases?

A)Internet applications using ASP
B)Internet applications using JSP
C)Applications invoking stored procedures
D)Programs coded in C#
E)All of the above are means of processing a database.

Question 33

Microsoft Access 2013 databases can be secured by deploying databases packaged with digital signatures.

Question 34

What concurrent processing problem occurs when a transaction reads a changed record that has not been committed to the database?

A)Nonrepeatable reads
B)Phantom reads
C)Dirty reads
D)Serialized reads
E)Unlocked reads

Question 35

The purpose of concurrency control is to:

A)ensure that each form has a corresponding report.
B)ensure that ASPs do not duplicate JSPs.
C)ensure that one user's work does not interfere with another's.
D)ensure that stored procedures do not invoke triggers.
E)ensure that triggers do not invoke stored procedures.

Question 36

Microsoft Access 2013 databases cannot be secured by password encryption.

Question 37

The term DBA refers to the:

A)database accessor.
B)database auditor.
C)data business auditor.
D)database administrator.
E)data business administrator.

Question 38

When a transaction functions in such a way that either all of the transaction actions are completed or none of them will be,the transaction is said to be:

A)consistent.
B)isolated.
C)atomic.
D)locked.
E)logical.

Question 39

Whether a lock applies to data at the record level,page level,table level,or database level is referred to as:

A)lock exclusivity.
B)lock sharing.
C)lock phasing.
D)serializable locking.
E)lock granularity.

Question 40

Preventing multiple applications from obtaining copies of the same record when the record is about to be changed is called:

A)serialized reading.
B)lost updating.
C)concurrent processing.
D)resource locking.
E)block factoring.

Question 41

When Microsoft Access 2013 creates a signed package with a digital signature,the database file will be a(n):

A)*.accdb file.
B)*.accdc file.
C)*.accde file.
D)*.mdb file.
E)*.mdw file.

Question 42

Database administrators must make sure that ________ measures are in place and enforced so that only authorized users can take authorized actions at appropriate times.

Question 43

Standard SQL defines four ________,which specify which of the concurrency control problems are allowed to occur.

Question 44

Which of the following is not true of database recovery through reprocessing?

A)Reprocessing makes use of a database save.
B)Reprocessing takes the same amount of time as did processing in the first place.
C)Reprocessing will always return the database to its exact previous state.
D)Reprocessing requires a record of all transactions since the last time the database was saved.
E)All of the above are true of reprocessing.

Question 45

Computer systems fail for which of the following reasons?

A)Hardware breaks.
B)Electrical power fails.
C)Programs have bugs.
D)People make mistakes.
E)All of the above

Question 46

When Microsoft Access 2013 uses user-level security with an Access 2003 file,the database is stored in a(n):

A)*.accdb file.
B)*.accdc file.
C)*.accde file.
D)*.mdb file.
E)*.mdw file.

Question 47

Serializable transactions are created by having a(n)________ phase,in which locks are obtained,and a(n)________ phase,in which locks are released.

Question 48

Additional DBA responsibilities include:

A)problem and error reporting.
B)requests of changes to existing systems.
C)controlling database configuration.
D)maintaining appropriate documentation.
E)All of the above

Question 49

The recovery technique in which the database is returned to a known state and then all valid transactions are reapplied to the database is known as:

A)reprocessing.
B)rollback.
C)transaction logging.
D)rollforward.
E)checkpointing.

Question 50

Transaction results are kept in a(n)________,which contains records of the data changes in chronological order.

Question 51

Breaking hardware,power outages,and human mistakes are all reasons that ________.

Question 52

When Microsoft Access 2013 secures a database with just a password,the database file will be a(n):

A)*.accdb file.
B)*.accdc file.
C)*.accde file.
D)*.mdb file.
E)*.mdw file.

Question 53

The recovery method where the database is restored using the saved data,and all transactions since the save are reapplied is called ________ recovery.

Question 54

Database administrators must make sure that ________ and ________ techniques and procedures are operating to protect the database in case of failure and to recover it as quickly and accurately as possible when necessary.

Question 55

When Microsoft Access 2013 secures a database just by storing the database in a trusted location,the database file will be a(n):

A)*.accdb file.
B)*.accdc file.
C)*.accde file.
D)*.mdb file.
E)*.mdw file.

Question 56

The recovery method in which we undo the changes that erroneous or partially processed transactions have made in the database is called ________ recovery.

Question 57

________ is an important business function whose purpose is to manage the database to maximize its value to the organization.

Question 58

When Microsoft Access 2013 compiles VBA code in a database,the database file will be a(n):

A)*.accdb file.
B)*.accdc file.
C)*.accde file.
D)*.mdb file.
E)*.mdw file.

Question 59

One of the major tasks of the database administration is called ________ control,which allows multiple users to access the database simultaneously.

Question 60

A point of synchronization between the database and the transaction log is called a(n):

A)before-image.
B)after-image.
C)recovery.
D)checkpoint.
E)None of the above

Question 61

What are the four transaction isolation levels?

Question 62

Distinguish between statement-level consistency and transaction-level consistency.

Question 63

What database administration functions help bring order to the potential chaos of the database processing environment?

Question 64

Microsoft Access 2013 can secure databases by using ________ to encrypt and decrypt the database files.

Question 65

Explain the process of using optimistic locking.

Question 66

Briefly explain the strategy of two-phased locking.

Question 67

Explain the concept of an "atomic transaction."

Question 68

Microsoft Access 2013 can secure database files by storing them in a(n)________.

Question 69

When Microsoft Access 2013 uses user-level security with an Access 2003 database file,it stores the database in a(n)________ file.

Question 70

Why do computers fail?

Question 71

What is the difference between authentication and authorization?

Question 72

Discuss Microsoft Access 2013 security administration.

Question 73

When Microsoft Access 2013 compiles VBA code in a database,the resulting file is stored using a(n)________ file extension.

Question 74

Briefly define the three problems that can occur because of concurrent processing that are addressed by resource locking.

Question 75

Microsoft Access 2013 can secure databases by deploying databases packaged with a(n)________.

Question 76

Distinguish between reprocessing and rollforward as database recovery techniques.