Database Management 7E Ch 7

Front 1

after image

Back 1

A record that the DBMS places in the journal or log that shows what the data in a row looked like in the database after a transaction update.

Front 2

authentication

Back 2

A technique for identifying the person who is attempting to access a DBMS.

Front 3

authorization rule

Back 3

A rule that specifies which user has what type of access to which data in a database.

Front 4

backup

Back 4

A copy of a database made periodically.

Front 5

backward recovery

Back 5

See rollback.

Front 6

batch processing

Back 6

The processing of a transaction file that contains a group of records to update a database or another file.

Front 7

before image

Back 7

A record that the DBMS places in the journal or log that shows what the data in a row looked like in the database before a transaction update.

Front 8

biometrics

Back 8

A technique to identify users of a database or other resource by physical characteristics such as fingerprints, voiceprints, handwritten signatures, and facial characteristics.

Front 9

commit

Back 9

A special record in a database journal or log that indicates the successful completion of a transaction.

Front 10

concurrent update

Back 10

A situation in which multiple users make updates to the same database at the same time.

Front 11

database password

Back 11

A string of characters assigned by the DBA to a database that users must enter before they can access a database.

Front 12

data dictionary

Back 12

A catalog, usually found in large, expensive DBMSs, that stores data about the entities, attributes, relationships, programs, and other objects in a database.

Front 13

data independence

Back 13

The property that lets you change the structure of a database without requiring you to change the programs that access the database.

Front 14

deadlock

Back 14

A situation in which two or more database users are each waiting to use resources that are held by others.

Front 15

deadly embrace

Back 15

See deadlock.

Front 16

decrypting

Back 16

A process that reverses the encryption of a database.

Front 17

encryption

Back 17

A security measure that converts the data in a database to a format that's indecipherable to normal programs. Decoded by the DBMS.

Front 18

forward recovery

Back 18

A process used to recover a database by reading the log and applying the after image of committed transactions to bring the database up to date.

Front 19

growing phase

Back 19

A phase during a database update in which the DBMS locks all the data needed for a transaction and releases none of the locks.

Front 20

journal

Back 20

A file that contains a record of all the updates made to a database. The DBMS uses the journal to recover a database that has been damaged or destroyed.

Front 21

journaling

Back 21

Maintaining a journal or log of all updates to a database.

Front 22

locking

Back 22

A DBMS's denial of access by other users to data while the DBMS processes one user's updates to the database.

Front 23

log

Back 23

A file that contains a record of all the updates made to a database. DBMS uses to recover a database that has been damaged or destroyed.

Front 24

metadata

Back 24

Data about the data in a database.

Front 25

nonprocedural language

Back 25

A language in which a user describes the task that is to be accomplished by the computer rather than the steps that are required to accomplish it.

Front 26

password

Back 26

A string of characters assigned by a DBA to a user that the user must enter to access a database.

Front 27

permission

Back 27

The specification of the kind of access a user has to the objects in a database.

Front 28

privacy

Back 28

The right of individuals to have certain information about them kept confidential.

Front 29

procedural language

Back 29

A language in which a user specifies the steps that are required for accomplishing a task instead of merely describing the task itself.

Front 30

recovery

Back 30

The process of returning a database to a state that is known to be correct from a state know to be incorrect.

Front 31

replica

Back 31

A copy of the data in a database that a user can access at a remote site.

Front 32

replicate

Back 32

A duplicate of the data in a database that a user can access at a remote site.

Front 33

rollback

Back 33

A process to recover a database to a valid state by reading the log for a problem transactions and applying the before images to undo their updates.

Front 34

save

Back 34

See backup.

Front 35

shrinking phase

Back 35

A phase during a database update in which the DBMS releases all the lock previously acquired for a transaction and acquires no new locks.

Front 36

smart card

Back 36

Small plastic cards about the size of a driver's license that have built-in circuits containing processing logic to identify the cardholder.

Front 37

synchronization

Back 37

The periodic exchange by a DBMS of all updated data between two databases in a replica set.

Front 38

timestamp

Back 38

The unique time when the DBMS starts a transaction update to a database.

Front 39

timestamping

Back 39

The process of using timestamps to avoid the need to lock rows in a database and to eliminate the processing time needed to apply and release locks and to detect and resolve deadlocks.

Front 40

transaction

Back 40

A set of steps completed by a DBMS to accomplish a single user task.

Front 41

two-phase locking

Back 41

An approach to locking that is used to manage concurrent update in which there are two phases: a growing phase, in which the DBMS locks more rows and releases none of the locks, and a shrinking phase, in which the DBMS releases all the locks and acquires no new locks.

Front 42

utility services

Back 42

DBMS-supplied services that assist in the general maintenance of a database.

Front 43

victim

Back 43

In a deadlock situation, the deadlocked user's transaction that the DBMS chooses to abort to break the deadlock.

Front 44

workgroup

Back 44

In Access, a group of users who are assigned the same permissions to various objects in a database.