Chapter 1: Databases and Database Users

Vocabulary flashcards covering key terms from Chapter 1 notes on databases, DBMS, architecture, and design concepts.

Database

A logically coherent collection of related data with inherent meaning, built for a specific purpose and representing an aspect of the real world.

DBMS (Database Management System)

A suite of programs that creates and maintains a database, defines data types, relationships, constraints, and stores metadata (data dictionary) in the database.

Schema

The structure of the database; a particular type of metadata.

Metadata

Data describing the structure, constraints, and characteristics of data in the database; stored within the database as catalog information.

Database Catalog

The metadata repository describing the database structure; used by DBMS and users.

Self-Describing Database

A database system that contains complete definitions of its structure and constraints within the DBMS.

Data Dictionary

Another term for metadata, describing data in the database.

Relation

A table in the relational model.

Entity Type

A class of entities in the real world; corresponds to a table.

Attribute

A property or field of an entity type; corresponds to a column.

Tuple

A row in a relation.

Table

A set of data records of the same format, divided into columns and rows.

View

A subset of columns (and possibly rows) from one or more related tables; not explicitly stored.

Stored Procedure

A set of SQL statements that can be parameterized and executed (like a macro).

SQL

Structured Query Language; language used to query and manipulate relational databases.

Relational Model

A data model based on relations (tables) with rows and columns.

ER Model (Entity-Relationship)

A conceptual data model used to describe entities and their relationships.

OODB (Object-Oriented Database)

A database model that stores objects rather than tables.

OLTP (Online Transaction Processing)

Applications involving routine transactions; requires concurrency control.

Transaction

An executing program that includes one or more database accesses; has isolation and atomicity properties.

Isolation

Each transaction appears to execute in isolation from other transactions.

Atomicity

All operations in a transaction are completed or none are.

Concurrency Control

Software that manages simultaneous data access by many users to ensure correctness.

DBA (Database Administrator)

Person responsible for authorizing access, coordinating use, and acquiring resources.

Database Designer

Person responsible for identifying data to store and choosing structures to represent it.

End User

People whose jobs require access to the database; types include casual, naive/parametric, sophisticated, and standalone.

System Analyst

Person who determines end-user requirements and develops canned transactions.

Application Programmer

Person who implements specifications as programs and maintains canned transactions.

Data Independence

Program-data independence; data structure is stored in the DBMS catalog separate from access programs.

Data Abstraction

Insulation between programs and data; data is abstracted by the DBMS.

Multiple Views

Ability to define several views of the data for different users; views are virtual and not stored.

Normalization

Process of organizing data to reduce redundancy and improve integrity.

Denormalization

Controlled redundancy introduced to improve query performance.

Impedance Mismatch

Mismatch between object-oriented languages and relational databases; OO DBMS try to address this.

Backup and Recovery

DBMS subsystem responsible for restoring data after failures.

Phase: Requirements Specification and Analysis

Initial phase in database design to determine user needs and system requirements.

Practical DBMS Products

Examples include PostgreSQL, MySQL (from Oracle), SQLite, Microsoft SQL Server; often used in coursework.