Introduction to Software Systems
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On this page
  • Data
  • Characteristics of Data
  • Types of Data
  • Importance of Data
  • Data Explosion
  • Entity Relationship Data Model
  • Importance of the ER Model
  1. Databases

Structured Databases

This page illustrates the details associated with structured databases

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Last updated 3 months ago

Data

It is refereed to a collection of discrete or continuous values that convey information. These values can describe various attributes such as quantity, quality, facts, and statistics. In essence, data serves as the raw material from which meaningful information can be derived.

Characteristics of Data

  • Raw vs. Processed: Raw data is unprocessed and may contain errors or outliers. It requires cleaning and organization before it can be analyzed effectively.

  • Structured vs. Unstructured:

    • Structured Data: Organized in a predefined format (e.g., databases), making it easy to search and analyze.

    • Unstructured Data: Lacks a specific format (e.g., text documents, images) and requires more complex processing to extract useful insights

Types of Data

Data can be classified into several categories:

  • Qualitative Data: This type describes qualities or characteristics and is often non-numerical (e.g., colors, textures).

  • Quantitative Data: This involves numerical values that can be measured (e.g., height, weight) and is further divided into discrete (countable) and continuous (measurable) data

Importance of Data

Data plays a crucial role in various fields including science, finance, marketing, and everyday decision-making. Its significance includes:

  • Decision Making: Data helps individuals and organizations make informed decisions based on factual evidence.

  • Problem Solving: Analyzing data allows for identifying issues and developing solutions.

  • Performance Evaluation: Organizations use data to assess their performance against goals.

  • Understanding Trends: Data analysis can reveal trends in consumer behavior, market dynamics, and more

Data Explosion

  • Annual Data Generation: This daily figure amounts to around 147 zettabytes generated per year

  • Growth Trends: The data generation rate is expected to continue increasing, with projections estimating around 181 zettabytes will be generated in 2025

The sources of this data are diverse, encompassing everything from social media interactions and video streaming to business transactions and IoT devices. For instance, in addition to the overall daily data creation, 361 billion emails are sent globally each day, and 16 million text messages are sent every minute. This rapid increase in data generation reflects the growing reliance on digital technologies and the internet in everyday life.

Entity Relationship Data Model

The Entity-Relationship (ER) model is a critical concept in structured databases, primarily used for designing and visualizing the structure of a database. Here’s an overview of the ER model, its components, and its significance in database management systems (DBMS). The ER model serves as a conceptual framework that illustrates how data elements relate to one another within a database. It was developed by Peter Chen in 1976 to provide a clear and straightforward method for representing data structures and relationships, making it easier for stakeholders to understand the database design before implementation. The ER model consists of three main components:

  1. Entities:

    • An entity represents a real-world object or concept that can be distinctly identified. For example, "Customer" or "Product" can be entities in a retail database.

    • Entities are typically depicted as rectangles in ER diagrams.

  2. Attributes:

    • Attributes are properties or characteristics that define an entity. For instance, a "Customer" entity may have attributes like "Customer ID," "Name," and "Email."

    • Attributes can be classified into different types, such as key attributes (unique identifiers), composite attributes (divisible into smaller parts), and derived attributes (calculated from other attributes).

  3. Relationships:

    • Relationships define how entities interact with one another. They can be categorized into types such as one-to-one, one-to-many, and many-to-many.

    • In ER diagrams, relationships are represented as diamonds connecting the relevant entities

Importance of the ER Model

  • Visual Representation: The ER model provides a graphical representation of the database structure, which helps in understanding how data is organized and related. This visualization aids in communication among technical and non-technical stakeholders

  • Database Design: It serves as a blueprint for constructing relational databases, allowing designers to plan the organization of data effectively before actual implementation

  • Reduction of Redundancy: By standardizing the representation of data, the ER model helps in minimizing redundancy and ensuring consistency across the database

  • Limitations: While the ER model is powerful, it has some limitations:

    • It may become complex for very large databases with numerous entities and relationships.

    • It does not adequately represent certain constraints between relationships or handle non-relational data efficiently

The Entity-Relationship model is integral to structuring databases effectively by translating conceptual data into relational formats. Entities become tables, attributes become columns, and relationships are established through foreign keys, facilitating organized data management and retrieval within structured databases. This mapping ensures that databases are designed efficiently, reflecting real-world relationships and constraints accurately.

In short, the world generates approximately 402.74 million terabytes of data every day, which translates to about 0.4 zettabytes. This immense volume includes newly created, captured, copied, and consumed information across various platforms and devices.To put this into perspective:

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Example for Entity Relationship Data Model
Various other Data Models to store Structured Data