Chapter 1: Database Systems

ad hoc query

"spur of the moment" question

knowledge

1. body of information and facts about a specific subject 2. implies familiarity, awareness, and understanding of information as it applies to an environment 3. key characteristic is that new knowledge can be derived from old knowledge

field

1. character or group of characters (alphabetic or numeric) that has specific meaning 2. used to define and store data

data quality

1. comprehensive approach to ensuring accuracy, validity, and timeliness of data 2. DBMS doesn't guarantee this, but instead provides framework to facilitate its initiatives

unstructured data

1. data that exists in its raw, original state; that is, the form in which it was collected 2. doesn't lend itself to processing that yields information

general-purpose database

1. database that contains wide variety of data used in multiple disciplines 2. EX: ProQuest database that contains wide variety of data used in multiple disciplines

cloud database

1. database that is created and maintained using cloud services, such as Microsoft Azure or Amazon AWS 2. these serves are provided by third party vendors and provide defined performance measure for database, but don't necessarily specify underlying infrastructure to implement it

data type

1. defines kind of values that can be used or stored 2. also, used in programming languages and database systems to determine operations that can be applied to such data

data redundancy

1. exists when same data is stored unnecessarily at different places 2. sets stage for poor data security, data inconsistency, data-entry errors, and lack of data integrity

data integrity

1. in relational database, condition in which data in database complies with all entity and referential integrity constraints 2. data is accurate and verifiable

extensible markup language (XML)

1. metalanguage used to represent and manipulate data elements 2. unlike other markup languages, it permits manipulation of document's data elements, allowing it to address storage and management needs of structured and semistructured data

NoSQL (Not only SQL)

1. new generation of DBMS that is not based on traditional relational database model 2. designed to handle unprecedented volume of data, variety of data types and structures, and velocity of data operations that are characteristic of these new business requirements

online analytical processing (OLAP)

1. one of two main components of analytical database 2. set of tools that work together to provide an advanced environment for retrieving, processing, and modeling data from data warehouse

data warehouse

1. one of two main components of analytical database 2. specialized database that stores historical and aggregated data in format optimized for decision support

advantages of DBMS

1. presenting data as single data repository promotes data sharing, thus eliminating potential problem of islands of information 2. enforces data integrity 3. eliminates redundancy 4. promotes data security

data management

1. process that focuses on data collection, storage, and retrieval 2. common functions include addition, deletion, modification, and listing

database design

1. process that yields description of database structure and determines database components 2. second phase of database life cycle

query

1. question or task asked by end user of database in form of SQL code 2. specific request for data manipulation issued by end user or application to DBMS 3. one of the advantages of DBMS because it allows for improved data access

limitations of file system data management

1. requires extensive programming 2. system administration can be complex and difficult, making changes to existing structures difficult 3. security features are likely to be inadequate 4. independent files tend to contain redundant data, leading to problems of structural and data dependence

database

1. shared, integrated computer structure that houses collection of released data 2. contains end user data (raw facts) and metadata

__________ consists of raw facts. __________ is the result of processing data to reveal its meaning.

Data; information

Information should be __________, __________, __________ to allow for good decision making.

accurate; timely; relevant

query result set

collection of data rows returned by query

database management system (DBMS)

collection of programs that manages database structure and controls access to data stored in database

file

collection of related records

data independence

condition in which data access is unaffected by changes in physical data storage characteristics

metadata

data about data that is stored in database

metadata

data about data; that is, data about data characteristics and relationships through which end user data is integrated and managed

structural dependence

data characteristic in which change in database schema affects data access, thus requiring changes in all access programs

structural independence

data characteristic in which changes to database schema don't affect data access

data dependence

data condition in which data representation and manipulation are dependent on physical data storage

semistructured data

data that has already been processed to some extent

structured data

data that has been formatted to facilitate storage, use, and information graphically

operational database (Online Transaction Processing Database, transactional database, production database)

database designed primarily to support a company's day-to-day operations

analytical database

database focused primarily on storing historical data and business metrics used for tactical or strategic decision making

centralized database

database located at single site

The __________ serves as the intermediary between the user and the database.

database management system (DBMS)

multiuser database

database that supports multiple concurrent users

single-user database

database that supports only one user at a time

discipline-specific database

database the contains data focused on specific subject areas

islands of information

in old file system environment, pools of independent, often duplicated, and inconsistent data created and managed by different departments

record

logically connected set of one or more fields that describes a person, place, or thing

distributed database

logically related database that is stored in two or more physically independent sites

workgroup database

multiuser database that usually supports fewer than 50 users or is used for a specific department in an organization

What are the ways in which a database can be classified?

number of users supported, where data is located, type of data stored, intended data usage, and degree to which data is structured

enterprise database

overall company data representation, which provides support for present and expected future needs

data processing (DP) specialist

person responsible for developing and managing computerized file system

data

raw facts, or facts that have not yet been processed to reveal their meaning to end user

information

result of processing raw data to reveal its meaning; consists of transformed data and facilitates decision making

business intelligence

set of tools and processes used to capture, collect, integrate, store, and analyze data to support business decision making

desktop database

single-user database that runs on personal computer

physical data format

way a computer "sees" (stores) data

logical data format

way a person views data within context of a problem domain

social media

web and mobile technologies that enable "anywhere, anytime, always on" human interaction