Databases - CS Fundamentals

Podcast

Play an AI-generated podcast conversation about this lesson

Download our mobile app to listen on the go

Get App

Questions and Answers

What is a primary key?

A method for organizing tables in a flat-file database.
A reference to a primary key in another table.
A non-unique identifier for records in a table.
A unique identifier for each record in a table. (correct)

Which statement correctly describes a flat-file database?

Uses entity relationship diagrams to visualize data relationships.
Organizes data into interconnected tables with relationships.
Utilizes primary and foreign keys to maintain data integrity.
Stores data as a single table with inflexible organization. (correct)

What is the main purpose of entity relationship diagrams (ERDs)?

To provide a visual representation of data relationships. (correct)
To eliminate data redundancy through normalization.
To store large datasets efficiently.
To enforce data integrity in a relational database.

Which describes normalization in a relational database?

The process of reducing redundancy and improving data integrity. (D)

Signup and view all the answers

What role does a foreign key play in a relational database?

It references the primary key of another table to create relationships. (A)

Signup and view all the answers

What is the purpose of indexing in a database?

To speed up data retrieval processes. (C)

Signup and view all the answers

What advantage do relational databases have over flat-file databases?

They allow for more flexible data organization and complex queries. (D)

Signup and view all the answers

What characterizes a secondary key in a database?

It allows for retrieving multiple records but is not unique. (B)

Signup and view all the answers

Flashcards

Flat-file databases

The simplest database type storing data in a single table where data organization is inflexible.

Entity Relationship Diagrams (ERDs)

Visual models representing entities and relationships in a database used for design.

Relational Database

Organizes data into multiple interconnected tables with predefined relationships.

Primary Key

A unique identifier for each record in a table, ensuring distinct entries.

Signup and view all the flashcards

Foreign Key

A field in one table referencing the primary key of another table to maintain relationships.

Signup and view all the flashcards

Secondary Key

A non-unique key that allows retrieval of multiple records, aiding querying.

Signup and view all the flashcards

Normalization

A process to reduce data redundancy and improve integrity by dividing tables and defining relationships.

Signup and view all the flashcards

Indexing

Data structures that speed up data retrieval, like an index in a book.

Signup and view all the flashcards

Study Notes

Databases - CS Fundamentals

Flat-file databases: Simplest database type. Store data in a single table (a flat file). Data organization is inflexible, making querying and updating challenging. Managing relationships between different pieces of information is difficult.
Entity Relationship Diagrams (ERDs): Visual models representing entities (objects) and relationships in a database. Used to design database structure before implementation. Show entities as rectangles, attributes as ellipses, and relationships as diamonds. Essential for database design.
Relational Database: Organize data in multiple interconnected tables. These tables have predefined relationships linking related data. Offers a structured approach for complex datasets, unlike flat files' limitations. Improves query capabilities, data integrity, and maintenance.
Flat File: A simple text file of data organized as rows and columns. Lacks a defined structure or relationships to other tables. Often used for small datasets or situations not needing complex structuring.
Primary Key: A unique identifier for each record in a table, ensuring each row is distinct. Critical for data integrity and record retrieval. Ex: Student ID in a student database.
Foreign Key: A field in one table referencing another table's primary key. Links tables and enforces referential integrity. Maintains data relationships.
Secondary Key: A non-unique key enabling retrieval of multiple records. Less critical to relational database integrity than primary and foreign keys, but speeds querying.
Entity Relationship Modelling: Designing a relational database by identifying entities, attributes, and relationships. Essential for converting data requirements into functional structures meeting user specifications.
Normalization: Reduces data redundancy and enhances data integrity in relational databases. Involves dividing large tables into smaller tables and defining relationships. Aims for a more efficient and structured database.
Indexing: Data structures improving data retrieval speed, acting like an index for a book. Significantly speeds up data searches and queries within the database.