Ch 1 Flashcards
Data vs information
Data are raw facts. Information is the result of processing raw data to reveal its meaning.
Data are the foundation of information, which is the bedrock of knowledge, i.e., the body of information and facts about a specific object.
Data management
Data management is a discipline that focuses on the proper generation, storage and retrieval of data.
Database
A database is a shared, integrated computer structure that stores a collection of the following:
- End-user data, i.e. raw facts of interest to the end user.
- Metadata, or data about data, through which the end-user data are integrated and managed.
Database management system (DBMS)
A database management system (DBMS) is a collection of programs that manages the database structure and controls access to the data stored in the database.
Advantages of the DBMS
Improved data sharing, improved data security, better data integration, minimized data inconsistency, improved data access, improved decision making, increased end-user productivity
Data inconsistency
Data inconsistency exists when different versions of the same data appear in different places.
Query & ad hoc query
A query is a specific request issued to the DBMS for data manipulation, e.g. to read or update the data. Simply put, a query is a question.
An ad hoc query is a spur-of-the moment question
Data quality
Data quality is a comprehensive approach to promoting the accuracy, validity and timeliness of the data. While the DMS does not guarantee data quality, it provides a framework to facilitate data quality initiatives.
Single-user database
A single-user database supports only one user at a time.
Desktop database
A single-user database that runs on a personal computer is called a desktop database.
Multiuser database
A multiuser database supports multiple users at the same time.
Workgroup database
When a multiuser database supports a relatively small number of users (usually less than 50), or a specific department within an organization, it is called a workgroup database.
Enterprise database
When a multiuser database is used by the entire organization and supports many users (more than 50, usually hundreds) across many departments, the database is known as an enterprise database.
Centralized database
A database that supports data located at a single site is called a centralized database.
Distributed database
A database that supports data distributed across several different sites is called a distributed database.