ITEC- CH4 auditing database systems

Query

Ad hoc access methodology for extracting information from a database

4 needed backup and recovery features

Backup- periodic backup of entire database stored in a remote location Transaction log- provides audit trail of all processed transactions Checkpoint- suspends all processing while system reconciled transaction log and database change log against database Recovery module- uses logs and backup files to restart the system after a failure

Data structures

Bricks and mortar of database Two components- organization and access methods

Database usage reporting

Captures statistics on database usage (who, when, etc.).

Replicated database

Common data replicated at each site (problem is maintains current versions of database at each site)

Backup and recovery

Copies made during processing

Data Manipulation Language (DML)

DML is the proprietary programming language that a particular DBMS used to retrieve, process, store data to/ from database

data redundancy which causes problems with

Data storage- data duplicated multiple times Data updating- changed must be made separately for each user (currency of information) Task- data dependency- users cannot obtain additional information as needs change

Access to the data resource is controlled by a

Database management system- centralizes orgs data into a common data base, eliminates data storage, data updating, and task-data dependency problem

Attributes

Defines entities with values that vary (each employee has a different name)

Conceptual view/ logical view (schema)

Describes the entire database logically and abstractly rather than physically. Only one conceptual view.

Hierarchical model (earliest) / navigational database

Each set contains a parent and a child Files at same level with the same parent are siblings Tree structure- with highest level in the tree being the root segment and lowest file being the leaf

Backup controls

Enables the company to recover its data if a disaster occurs

One -to many- record type

For every record type x- there are many occurrences of record type y Customer record , sales order record

One to one record type

For every record type x- there is one record type y Employee record- year to data earnings

Many-to many association

Inventory record to vendor record

Flat file approach

Large, older legacy systems still in use today Promotes a single- user view approach where end users own rather than share data files

Physical data base is at what level

Lowest level- only in physical form

Deadlock Phenomenon

Occurs when multiple sites lock each other out of the database preventing each from processing its transactions (permanent condition must be solved with special software)

Internal view/ Physical database view

Physical arrangement of records in the database

Record type

Physical database representation of an entity

External view/ User view (subschema)

Portion of database each user views. May be many distinct users.

Relational model

Portrays data in two- dimensional tables with attributes across the top performing columns Intersecting columns to form rows are tuples

Concurrency control

Presence of complete and accurate data at all user sites,

Data Encryption

Protect sensitive data

Occurrence

Related to number of records of represented by a particular record type

Database

Set of record types that an organization needs to support its business processes

Data Definition Language (DDL)

Used to define the database to the DBMS on three levels

Partitioned database advantages

Users control increased Improved transaction processing response time Volume of transmitted data Between IT units reduced Reduces potential data loss from a disaster

User-defined procedures

allow user to create a personal security program or routine to provide identification

Partitioned database

database approach that splits the central database into segments or partitions that are distributed to their primary users Works best for orgs that require minimal data sharing among units

user view (subschema)

defines how a user sees the portion of the database user is authorized to access

Access controls

designed to protect systems from unauthorized access in order to preserve data integrity

Biometric devices

fingerprints, retina prints, or signature characteristics

Database lockout

prevents two applications or users from updating the same file at the same time

Inference controls

should prevent users from inferring, through query options, specific data values they are unauthorized to access

Database Authorization Table

table containing rules that limit the actions a user can take

Entity

Anything organization wants to capture data about

Program development

Applications may be created by programmers and end users