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Data Model

A relatively simple representation, usually graphical, of more complex real-world data structures.

Desktop Database

A single-user Database that runs on a personal computer.

Extensible Markup Language (XML)

A special language used to represent and manipulate data elements in a textual format.

Data Warehouse

A specialized database that stores data in a format optimized for decision support. Contains historical data obtained from the operational databases as well as data from other external sources.

Heap Files

Files containing an unsorted set of records that are uniquely identified by a record ID which allows them ot be inserted or deleted using that ID

Flat Files

Files having no internal hierarchy. Plain text files or binary files.

Index Files

Files that store a list of lookup field values from a data file- along with the location(address)in the data file of the corresponding record

Hashed Files

Files which use a hash function to decide where a record should be places on a disk. This allows for faster data lookup without the use of an index files

Database Design

Refers to the activities that focus on the design of the database structure that will be used to store and manage end-user data.

Performance Testing

Relates to the activities that make the database perform more efficiently in terms of storage and access speed.

Structural Independence

When you can change the file structure without affecting the application's ability to access the data.

File-Based Systems

Where Information was stored before Database Management Systems

Better Data Integration

Wider access to well-managed data promotes and integrated view of the organizations operations and clearer view of the big picture. It becomes much easier to see how actions in one segment of the company affect other segments.

Online Analytical Processing (OLAP)

a set of tools that work together to provide an advanced data analysis environment for retrieving, processing, and modeling data from the data warehouse.

End-user data

Raw facts of interest to the end user

Field

A character or group of characters(alphabetic or numeric) that has a specific meaning. A field is used to define and store data.

Record

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

Ubiquitous Data

Abundant, Global, Everywhere

Structural Dependence

Access to a file is dependent on its structure. A data characteristic in which a change in the database schema affects data access, thus requiring changes in all access programs.

Key to Good Decision Making.

Accurate, Relevant, and Timely Information.

Improved Decision Making

Better-managed data and improved data access make it possible to generate better-quality information, on which better decisions are based.

Database Management System(DBMS)

Collection of programs that manages the database structure and controls access to the data stored in the database. Manges the database structure and interacts with the users, and the database itself to analyze data. It controls access to the data stored in the database.

Data Quality

Comprehensive approach to promoting the accuracy, validity, and timeliness of the data

General-Purpose Databases

Contain a wide variety of data used in multiple disciplines

Disciple-Specific Databases

Contain data focused on specific subject areas.

Cloud Database

Created and maintained suing cloud data services EX: Microsoft Azure or Amazon AWS

Database Communication Interfaces

Current DBMSs accept end-user requests via multiple different network environments.

Improved data sharing

DBMS helps create an environment in which end users have better access to more and better-managed data. Such access makes it possible for end users to respond quickly to changes in the their environment.

Improved Data Security

DBMS provides a framework for better enforcement of data privacy and security policies

Metadata

Data about data, through which the end-user data is integrated and managed. Describes the data characteristics and the set of relationships that link the data found within the database. Stores information such as the name and the type of values stored on each data element. It provides information that expands the value and the use of the data.

Unstructured Data

Data that exists in its original, raw state; that is, in the format in which it was collected.

Operational Database(Online Transaction Processing (OLTP) Database

Database that is deigned primarily to support a company's day-to-day operations

Structured Query Language (SQL)

De facto query language and data access standard supported by the majority of DBMS vendors.

Business Intelligence

Describes a comprehensive approach to capture and process business data with the purpose of generating information to support business decision making.

System Analysts and Programmers

Design and implement the application programs. They design and create the data-entry screens, reports, and procedures through which end users access and manipulate the database's data.

Data Management

Discipline that focuses on the proper generation, storage, and retrieval of data. Comprises all the facts and figures related to managing and analyzing data. It focuses on data collection, storage and retrieval.

Advantages of DBMS

Enables the data in the database TO BE SHARED among multiple applications or users. The DBMS integrates the many different users' views of the data into a single all-encompassing data repository.

Analytical Database

Focuses primarily on storing historical data and business metrics used exclusively for tactical or strategic decision making. Allows the end user to perform advanced analysis of business data using sophisticated tools.

NOSQL(Not Only SQL)

Generally used to describe a new generation of database management systems that is not based on the traditional relational database model. Designed to handle the unprecedented volume of data, variety of data types and structures, and velocity of data operations that are characteristic of these new business requirements.

Semi-structured Data

Has already been processed to some extent.

Physical Data Format

How the computer must work with the data.

Logical Data Format

How the human being views the data.

Manual File System

Includes paper-and-pencil system to facilitate the expected use of data.

Good decision making

Key to business survival in a global market.

Improved Data Access

Makes it possible to produce answers to ad hoc queries.

Database Administrator (DBA)

Manage the DBMS and ensure that the database if functioning properly.

Query Language

Nonprocedural language(one that lets the user specify what must be done without having to specify how).

System Administrators

Oversee the database system's general operations.

End Users

People who use the application programs to run the organization's daily operations.

Data

Raw Facts. Facts have not been processed to reveal their meaning. Building blocks of information.

Database

Shared, integrated computer structure

Query

Specific request issued to the DBMS for data manipulation. Simply put, query is a question.

Ad Hoc Query

Spur-of-the-moment question.

Islands of Information

Storage of the same basic data in different locations.

Computerized File Systems

Stores and organizes computer files and makes data easy to find and access them. Generates reports and keeps track of complex data.

Distributed Database

Supports data distributed across several different sites.

Centralized Database

Supports data located at a single site.

Multiuser Database

Supports multiple users at the same time

Single-User Database

Supports only one user at a time. EX: If user A is using the database, users B and C must wait until user A is done.

XML Database

Supports the storage and management of semi-structured XML data.

Security Management

The DBMS creates a security system that enforces user security and data privacy.

Data Storage Management

The DBMS creates and manages the complex structures required for data storage, thus relieving you from the difficult task of defining and programming the physical data characteristics. Important for Performance Testing.

Data Integrity Management

The DBMS promotes and enforces integrity rules, thus minimizing data redundancy and maximizing data consistency.

Backup and Recovery Management

The DBMS provides backup and recovery to ensure data integrity.

Database Access Languages and Application Programming Interfaces

The DBMS provides data access through a query language.

Data Dictionary Management

The DBMS stores definitions of the data elements and their relationships(metadata) in a data dictionary. In turn, all programs that access the data in the database work through the DBMS. Provides data abstraction, and it removes structural and data dependence from the system.

Data Transformation and Presentation

The SBMS transforms entered data to conform to required data structures. Relives you of the chore of distinguishing between the logical data format and the physical data format.

Structured Data

The result of formatting unstructured data to facilitate storage, use, and the generation of information

Increased End-User Productivity

The availability of data, combined with the tools that transform data into usable information, empowers end users to make quick, informed decisions that can make the difference between success and failure in the global economy.

Knowledge

The body of information and facts about a specific subject. Implies familiarity, awareness, and understanding of information as it applies to an environment.

Data Integrity

The condition in which all of the data in the database is consistent with the real-world events and conditions.

Verifiable Data

The data will always yield consistent results.

Data Modeling

The first step in designing a database, refers to the process of creating a specific data model for a determined problem domain.

File Structure

The format that data is arranged and store din a file

Minimized Data Inconsistency

The probability of data inconsistency is greatly reduced in a properly designed database.

Information

The result of processing RAW data to reveal its meaning. Simple as organizing data to reveal patterns or as complex as making forecasts or drawing inferences using statistical modeling. Requires context. Produced by processing data.

Accurate Data

There are no data inconsistencies.

Multiuser Access Control

To provide data integrity and data consistency, the DBMS uses sophisticated algorithms to ensure that multiple users can access the database concurrently without compromising its integrity.

Pervasive Data

Unescapable, Prevalent, Persistent

Query Result Set

What the DBMS sends back to the application.

Data Dependence

When data access programs are subject to change when any of the files data storage characteristics change. Data condition in which data representation and manipulation are dependent on the physical data storage characteristics. It makes file systems extremely cumbersome from a programming and data management point of view.

Data Inconsistency

When different versions of the same data appears in different places

Data Anomaly

When not all of the required changes in the redundant data are made successfully.

Enterprise Database

When the multiuser database is used by the entire organization and supports many users(more than 50, usually hundreds)across many departments.

Workgroup Database

When the multiuser database supports a relatively samll number of users(usually fewer than 50) or a specific department within an organization.

Data Redundancy

When the same data is stored unnecessarily at different places.

Data Independence

When you can change the data storage characteristics without affecting the program's ability to access the data.