Data Models: Importance, Building Blocks, and Evolution

Business rules

A brief, precise, and unambiguous description of a policy, procedure, or principle within a specific organization.

Invoice generation rule

A business rule stating that a customer may generate many invoices and an invoice is generated by only one customer.

Attributes

A characteristic of an entity (fields in a table).

Problem domain

A clearly defined area within the real-world environment, with a well-defined scope and boundaries that will be systematically addressed.

Entity Relationship Model

A conceptual framework for data relationships.

Communication tool

A function of data models that facilitates interaction among the designer, the applications programmer, and the end user.

Entity

A noun representing an object in the model.

Entities

A person, place, thing, concept, or event about which data will be collected and stored.

Crow's Foot notation

A popular ER diagram notation using symbols.

Lucidchart

A powerful database design tool used to diminish the potential for errors in database modeling.

Many-to-many relationship

A relationship where many occurrences of one entity can be associated with many occurrences of another entity (M:N or *..*).

One-to-many relationship

A relationship where one entity can be associated with many occurrences of another entity (1:M or 1..*).

One-to-one relationship

A relationship where one entity is associated with exactly one occurrence of another entity (1:1 or 1..1).

Data model

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

Constraints

A restriction placed on the data to help ensure data integrity.

MapReduce

API for fast data analytics services.

Inheritance

Ability to inherit attributes and methods.

Object

Abstraction of a real-world entity.

Method

Action performed by a class, like finding names.

Chen notation

An ER notation for data modeling.

Relationships

An association among entities based on business rules.

Customer entity

An entity representing a customer, which has many distinguishable occurrences such as John Smith, Pedro Dinamita, and Dana Strickland.

Student GPA constraint

An example of a constraint that states a student's GPA must be between 0.00 and 4.00.

Employee salary constraint

An example of a constraint that states an employee's salary must have values between 6,000 and 350,000.

Class teacher constraint

An example of a constraint that states each class must have one and only one teacher.

Database blueprint

An overall design plan for a database based on an appropriate data model.

Logical independence

Change internal model without affecting conceptual model.

Physical independence

Change physical model without affecting internal model.

Attribute

Characteristic or property of an entity.

Class

Collection of similar objects with shared behavior.

Attribute (in Relational Model)

Column in a relational database table.

Object-Oriented Data Model

Combines data and relationships in objects.

Schema

Conceptual organization of the entire database.

Relationship

Connection between entities, defined by verbs.

Object/Relational DBMS

DBMS combining relational and object-oriented features.

Relational Model

Data model based on mathematical relations.

Internal model

Database representation as seen by DBMS.

Data Definition Language (DDL)

Defines schema components in a database.

Physical model

Describes data storage on physical media.

Naming Convention

Descriptive naming for entities and attributes.

NoSQL

Distributed database for structured and unstructured data.

Invoice

Document generated by a customer for purchases.

Database Performance

Efficiency of data retrieval and management.

External schema

End users' view of the data environment.

Customer

Entity that generates invoices in the model.

Communication Tool

Facilitates dialogue between users and designers.

Hadoop Distributed File System

Fault-tolerant file system for large data.

Degrees of Data Abstraction

Framework defining external, conceptual, internal levels.

Conceptual schema

Global view of database across business units.

Entity Relationship Model (ERM)

Graphical representation of entities and relationships.

Business Rules

Guidelines from managers and documentation for data use.

Extended Relational Data Model

Integrates OO features into relational databases.

Hadoop

Java-based framework for distributed data processing.

Connectivity

Labels relationship types in the ER model.

Data Manipulation Language (DML)

Language for managing and manipulating database data.

Controlled Redundancy

Minimized duplication of data in databases.

Big Data

Movement for managing large data volumes.

Internet of Things

Network of connected devices exchanging data.

One-to-Many Relationship

One entity relates to multiple instances of another.

Data Structures

Organized formats for storing and managing data.

Subschema

Portion of the database visible to applications.

Relational model

Preferred model for business applications.

Bidirectional relationships

Relationships that can be identified in both directions.

Network model

Replaced hierarchical model for complex relationships.

Tuple

Row in a relational database table.

Business Process

Series of tasks to achieve a business goal.

Extensible Markup Language

Standard for exchanging structured data.

Unified Modeling Language

Standard for modeling software systems.

Data Model

Structured representation of data relationships and rules.

Object-oriented data model

Supports complex data within semantic framework.

Relational Database Management System (RDBMS)

System managing relational database structures.

Data integrity

The accuracy and consistency of data stored in a database.

Data transformation

The process of converting data into information through applications.

Data modeling

The process of creating a specific data model for a determined problem domain.

Class diagram notation

UML representation of classes and relationships.

Standardization

Uniform data interpretation across the organization.

Class hierarchy

Upside-down tree structure of classes.

Graphical Tool

Visual aid for designing complex databases.

Entity Relationship Diagram (ERD)

Visual tool for modeling database components.

3 Vs

Volume, velocity, variety of Big Data.