ICS2607 Information Management - Database Systems Flashcards

35 practice Q&A flashcards covering fundamental concepts from the lecture notes on database systems.

What is the difference between data and information?

Data are raw facts; information is processed data that reveals meaning and requires context.

What are the two components stored in a database?

End-user data and metadata (data about data) describing data characteristics and relationships.

What does a DBMS do?

A collection of programs that manages the database structure and controls access to data.

Why are databases valuable for decision making?

They provide organized, accurate, timely information derived from data, supporting better decisions.

What is the DBMS's role as intermediary?

It sits between users and the database, enabling data sharing and providing multiple users' views of data.

Name two classifications of databases by user load.

Single-user (desktop) databases and multi-user (workgroup and enterprise) databases.

What is a centralized database?

Data located at a single site.

What is a distributed database?

Data distributed across several different sites.

What is an operational (transactional) database?

A database that supports day-to-day operations and transactional processing.

What is a data warehouse used for?

Stores data used for tactical or strategic decision making.

What is unstructured data?

Data that exist in its original state, not formatted or organized.

What is structured data?

Data that have been formatted or organized based on processing requirements.

What is semi-structured data and XML in this context?

Semi-structured data has been processed to some extent; XML represents data elements in textual format and XML databases support such data.

Why is database design important?

Well-designed databases facilitate data management and generate accurate and valuable information; poor design leads to errors.

What is the Evolution of File System Data Processing?

Studying file systems helps understand DBMS design; file systems evolved from manual to computerized, with files having their own applications.

What is a file system in data processing terms?

A collection of files/folders organized for storage, often with per-file programs, owned by departments.

What were common problems with file systems?

Ad hoc queries were hard or impossible; updating structure was difficult; security features were hard to program.

What is structural dependence?

Access to a file depends on its internal structure; changes to structure require modifying programs.

What is data dependence?

Access to data changes when storage characteristics change.

What is data independence?

Data storage characteristics do not affect data access.

What is data redundancy?

The same data stored in multiple places, leading to islands of information and update anomalies.

What are data anomalies?

Abnormalities when changes to redundant data are not done consistently, including update, insertion, deletion anomalies.

Why are data-modeling skills vital?

They facilitate communication among designer, user, and developer and improve design quality.

What are the five major parts of the database system environment?

Hardware, Software, People, Procedures, Data.

What is a data dictionary?

DBMS stores definitions of data elements and relationships (metadata) and uses it to support data abstraction; changes are recorded automatically.

What is SQL and its role?

Structured Query Language; the de facto nonprocedural language used to query and manage databases.

What are database communication interfaces?

Methods by which DBMS connects with end-users and other systems, enabling forms, reports, and distribution.

What is the shift in focus in managing a database system?

From programming to managing the organization’s resources, processes, and data.

Name some roles in the database system environment.

End users, database administrator, analysts, designer, programmers.

What is data storage management in the DBMS?

DBMS creates and manages storage structures and related forms, screens, and reports; data is stored in multiple physical files.

What is security management in the DBMS?

DBMS enforces security and data privacy; defines which users can access which data.

What is multiuser access control?

DBMS uses algorithms to ensure concurrent access does not compromise data integrity.

What is backup and recovery management?

DBMS provides backup and recovery mechanisms to preserve data integrity after failures.

What is data integrity management?

DBMS enforces integrity rules to minimize redundancy and maximize consistency; data relationships in the data dictionary help enforce integrity.

What are database access languages and what is the de facto standard?

Query languages; Structured Query Language (SQL) is the de facto standard.

What are database communication interfaces used for?

They allow end-users to access data via screens, reports, and distribution via networks or the web.

What is metadata in a DBMS?

Data about data describing data characteristics and relationships, stored in the data dictionary.

How does DBMS support data sharing?

By managing access to the database and providing multiple user views while maintaining integrity.

What is the impact of database technology on system selection?

Affects cost-effectiveness, tactical and strategic effectiveness of the chosen database solution.

What is meant by 'islands of information'?

Data stored in different locations with little or no integration.

What is a data field?

A character or group of characters with a specific meaning used to store data.

What is a database career example and a skill required?

Database administrator — skills in DBMS fundamentals, SQL, and data security technologies.