Data Modeling Chapter 2: Data Models

Entity Relationship (ER) Model (ERM)

A data model that describes relationships among entities at the conceptual level with the help of ER diagrams. The model was developed by Peter Chen.

Segment

A file system's record type.

Relationship

A relationship describes the association between entities.

Connectivity

A type of relationship between entities.

Tuple

Rows.

Subschema

defines the portion of the database seen by the application programs that produce the desired information from the data within the database.

Entity Set

A Collection of like entities

data model

A data model is commonly a graphic representation of a complex real-world data structure that is used in the design phase of the database.

Class

A group of like objects that share structure and behavior broken into hierarchies

Relation

A mathematical concept also known as a table; composed of intersecting rows and columns.

Extended relational data model (ERDM)

A model that includes the object-oriented model's best features in an inherently simpler relational database structural environment.

NoSQL

A new generation of database management systems that is not based on the traditional relational database models.

business rule

A policy to create and enforce actions

Crow's Foot Notation

A representation of the entity relationship diagram that uses three-pronged symbols to represent sides of the relationship.

Hierarchical model

A reverse tree model that shows relationships from a top to bottom approach. The top segment is the root segment, and every segment under that has a one-to-many relationship with the one below them.

Object

An abstract representation of a real world entity that has a unique identity, embedded properties, and the ability to interact with other objects and itself.

Tuple

Each Row in a relational model.

SQL-Based Relational Database Application

End-user interface allows the end user to interact with the data. Collection of tables are stored in the database, while each table is independent from another. Rows in different tables are related based on common values in common attributes, and SQL engine executes all queries.

Schema data definition language (DDL)

Gives a database's Admin the ability to provide defined schema elements

constraint

Holding the data back

Unified Modeling Language (UML)

It is a language that is based on object-oriented concepts that provide tools. This includes diagrams and symbols that graphically model a system.

Big Data

Newer and better ways to manage large amounts of web and sensor-generated data and pull business insight from it, while also allowing for high performance and scalability at a decent cost.

Relational Database Management System (RDBMS)

Performs basic functions provided by the hierarchical and network DBMS systems, makes the relational data model easier to understand and implement, and hides the complexities of the relational model from the user.

SQL Engine

Runs all the queries

schema

The database Administrator's view of the organizational concept of the database as a whole

American National Standards Institute (ANSI)

The group that accepted the DBTG recommendations and augmented database standards in 1975 through its SPARC committee.

Entity

The person place thing or event that the data is collected for. This is one of the basic building blocks of data modeling.

method

This is a set of procedures that perform an action. They typically represent real-world actions and are brought up through messages.

Variety

This is in reference to numerous data formats currently being collected that are not suitable for typical operational databases in the relational model

Volume

This is in reference to the amount of data that is easily accumulated and stored on the internet and social media. Databases are growing to petabytes in size an beyond.

Velocity

This is in reference to the increasing speed that companies need to access, process and retrieve their data.

data modeling

This is the first step in designing a database, which is referring to the process we use to create a specific data model as a solution for a defined issue.

Sparse data

a case in which the number of table attributes is very large but the number of actual data instances is low

class diagram

a diagram that is used to represent data and their relationships in UML object notation

Hadoop

a java based , open source , high speed , fault-tolerant distributed storage and computational framework.

one-to-many relationship

a relationship that describes one entity associating with two or more other instances; 1:M; 1..*

one-to-one relationship

a relationship that describes one entity instance associating with only one other instance in a related entity; 1:1; 1..1

many-to-many relationship

a relationship that describes two or more entities associating with another two or more instances; M:N; *..*

Attribute

characteristic for anything

Class

collection of similar objects with shared structure (attributes) and behavior (methods)

data node

data node connects to a name node spinning until the service comes up

Entity relationship diagram (ERD),

graphical representations to model database components.

Network model

is a database model the represents objects and the relationships.

Relational diagram

is a representation of the relational database's entities, the attributes within those entities, and the relationships between those entities.

Relational database management system (RDBMS)

same basic functions provided by the hierarchical and network DBMS systems

data management language (DML),

which defines the environment in which data can be managed and to work with the data in the database.