Database Principles: Topic 1 - The Database Approach

These flashcards cover the fundamental concepts of database principles, including definitions of data and information, the roles of a DBMS, types of databases, file system evolution, and the components of the database system environment.

What is the relationship between data and information?

Data are raw facts, while information is the result of processing raw data to reveal meaning.

What is required for information to reveal meaning?

Context

What is the definition of a database?

A shared, integrated computer structure that stores a collection of end-user data and metadata.

How is metadata defined?

Data about data; it provides a description of data characteristics and relationships in data.

What is a database management system (DBMS)?

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

Why is the DBMS considered an intermediary between the user and the database?

The database structure is stored as a file collection that can only be accessed through the DBMS.

What are some advantages of using a DBMS?

Improved data sharing, improved data security, better data integration, minimized data inconsistency, improved data access, improved decision making, and increased end-user productivity.

What is a desktop database?

A single-user database that runs on a PC.

What is the difference between a centralized database and a distributed database?

A centralized database has data located at a single site, while a distributed database has data distributed across several different sites.

What is an operational database?

A database that supports a company’s day-to-day operations, also known as a transactional or production database.

What is the purpose of a data warehouse?

To store data used for tactical or strategic decisions.

What is the difference between unstructured and structured data?

Unstructured data exists in its original state, while structured data results from formatting applied based on processing needs.

What does XML stand for and what type of data does it represent?

Extensible Markup Language; it represents semistructured data elements in textual format.

What are the three reasons for studying file systems?

To understand the complexity of database design, to avoid problems with DBMS systems, and to gain knowledge useful for converting file systems to database systems.

What is structural dependence?

A condition where access to a file is dependent on its own structure, requiring all programs to be modified if the file structure changes.

What is the difference between logical data format and physical data format?

Logical data format is how a human views the data, while physical data format is how the computer must work with the data.

What is data redundancy?

The condition where the same data is stored unnecessarily in different places.

What are data anomalies?

Abnormalities that occur when all changes in redundant data are not made correctly, specifically update, insertion, and deletion anomalies.

What is a database system?

A system that consists of logically related data stored in a single logical data repository, defining and regulating the collection, storage, management, and use of data.

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

Hardware, software, people, procedures, and data.

What three types of software are required in a database system?

Operating system software, DBMS software, and application programs and utility software.

What is the function of data dictionary management in a DBMS?

The DBMS stores definitions of data elements and their relationships in a data dictionary, providing data abstraction and removing structural/data dependency.

What is performance tuning as a DBMS function?

Activities that make the database perform more efficiently.

What is the de facto query language standard supported by most DBMS vendors?

Structured Query Language (SQL)

What are the disadvantages of database systems?

Increased costs, management complexity, maintaining currency, vendor dependence, and frequent upgrade/replacement cycles.