Week 1A - Database Applications, Terminology, and History

Question 1

Examples of Database Applications

Answer 1

Traditional database applications (banks, library catalogs, inventory, airlines, universities)

Multimedia Databases (images, video)

Geographic info systems

Data warehouse and online analytical processing (OLAP)

Real time and active DB technology (sensor systems, safety-critical systems)

World wide web (e-commerce, internet banking)

Question 2

Define data

Answer 2

Known facts that can be recorded

Question 3

Define database

Answer 3

Logically coherent collection of related data with some inherent meaning

Question 4

Provide examples of ‘entities’

Answer 4

Students, courses, sections (seminars, modules)

Question 5

Provide examples of ‘relationships’ between entities

Answer 5

Students taking courses, and sections (seminars, modules) being part of courses

Question 6

Define Database Management System

Answer 6

Collection of programs that enable users to create and maintain a DB

Question 7

[EARLY 60s] Who was Charles Bachman and what was his major achievement?

Answer 7

He was one of the first pioneers of database technology.

He won the Turing Award in 1973 for developing the Integrated Data Store (IDS) and creating the Network Data Model.

Question 8

[EARLY 60s] What was the Network Data Model?

Answer 8

A database model that represented data using records connected through “sets”, allowing complex many-to-many relationships between data. It was more flexible than hierarchical models but more complex to manage.

Question 9

[EARLY 60s] What was CODASYL?

Answer 9

CODASYL (Conference on Data Systems Languages) was a consortium that standardized the Network Model, similar to how SQL would later be standardized for relational databases.

Question 10

[LATE 60s] What was IMS?

Answer 10

Information Management System (IMS) was one of the first major database management systems.

Question 11

[LATE 60s] Who developed IMS?

Answer 11

IBM

Question 12

[LATE 60s] What was the Hierarchical Data Model?

Answer 12

A database model that organized data in a tree-like structure where each record could have only one parent but multiple children, similar to how a file system organizes folders and files.

Question 13

[LATE 60s] What was the main limitation of the Hierarchical Model?

Answer 13

The main limitation was that each child record could only have one parent record, making it difficult to represent many-to-many relationships or complex data structures.

Question 14

[1970s] Who was Edgar Codd and what was his contribution?

Answer 14

Edgar Codd won the Turing Award in 1981 for introducing the Relational Data Model at IBM. His work revolutionized database technology and laid the foundation for modern databases.

Question 15

[1970s] What was revolutionary about the Relational Data Model?

Answer 15

It represented data in simple tables (relations) with rows and columns, making data manipulation more mathematical and logical. This was simpler to understand and more flexible than previous models.

Question 16

How did the database models progress from 60s to 70s?

Answer 16

The progression went from Network Model (complex relationships but complicated) → Hierarchical Model (simple but limited) → Relational Model (flexible and mathematically sound).

Question 17

What were the main differences between Network and Hierarchical models?

Answer 17

Network Model allowed many-to-many relationships through sets, while Hierarchical Model only allowed one-to-many relationships through parent-child structures. Network was more flexible but more complex.

Question 18

Why did the Relational Model eventually succeed over earlier models?

Answer 18

• It was simpler to understand and use
• It had a strong mathematical foundation
• It provided more flexibility in data relationships
• It enabled easier data manipulation through what would become SQL

Question 19

[1980s] What major shift happened in database models during the 80s?

Answer 19

The Relational Data Model became dominant, replacing the older tree-based and graph-based models.

Question 20

[1980s] What significant language emerged in the 80s?

Answer 20

SQL (Structured Query Language) became the standard language for relational databases.

Question 21

[1980s] Who was James Gray and what was his contribution?

Answer 21

James Gray won the Turing Award in 1999 for his pioneering work on Transaction Management, which revolutionized how databases handle multiple users working with data simultaneously.

Question 22

[1980s] What is ACID?

Answer 22

Atomicity: Transactions are all-or-nothing operations
Consistency: Data remains valid after the transaction
Isolation: Transactions don’t interfere with each other
Durability: Completed transactions are permanent

Question 23

[1980s] Why is ACID important?

Answer 23

ACID ensures reliable database operations when multiple users are accessing and modifying data simultaneously.

Question 24

[1980s] What is Transaction Management and why was it important?

Answer 24

Transaction Management was a crucial development that:

Allowed multiple users to work with the same data simultaneously without conflicts
Ensured data remains consistent even if system failures occur
Introduced the concept of transactions as atomic units of work
Enabled modern applications like banking systems and airline reservations where data integrity is critical

Question 25

[1980s] Define SQL

Answer 25

A specialized programming language designed for managing and manipulating data stored in relational databases.

Question 26

[1990s] What new database model was predicted to replace the relational model?

Answer 26

The Object-oriented Data Model was believed to be the successor to the relational model (though this prediction didn’t fully materialize)

Question 27

[1990s] What were the major developments in database applications during the 90s?

Answer 27

• Data warehousing and Business Intelligence
• Database marketing
• Data mining
• Multimedia data handling
• XML (both native XML databases and XML in relational databases)

(might need to expand on these)

Question 28

[1990s] What was significant about XML in databases?

Answer 28

XML introduced a new way to store and structure data, leading to two approaches:

• XML-native databases
• XML support within relational databases

(might need to expand on what xml is)

Question 29

[2000s] How did the web impact databases in the 2000s?

Answer 29

Databases became accessible through web/internet interfaces.

(could need more content)

Question 30

[2000s] What was the main focus of database development in the 2000s?

Answer 30

Content management became a major focus, with systems needed to handle increasing amounts of web content and digital assets.

Question 31

What are the two main focuses of modern database development?

Answer 31

Big Data
Machine Learning and AI integration with databases

Question 32

Big Data

Answer 32

Handling extremely large datasets

Question 33

How has the approach to choosing database systems changed from past to present?

Answer 33

In the past, companies tried to choose the best single data model and system. Nowadays, companies must be capable of handling multiple data models and formats, with systems that can readily exchange data.

Question 34

What are the main data formats used today?

Answer 34

CSV (Comma-separated values)
XML (e.g., <student><name>Sue</name></student>)
JSON (e.g., { “firstName”: “Peter”, “age”: 30 })
Relational formats

Question 35

How have relational concepts influenced other data models?

Answer 35

Key relational concepts like primary and foreign keys have been adopted by other formats (JSON, XML, document stores, etc.)

Question 36

What is the modern approach to data exchange?

Answer 36

Import and export data in any format
Handle multiple data models simultaneously
Exchange data between different systems seamlessly

Question 37

What is the significance of Big Data and ML in modern databases?

Answer 37

These technologies have pushed databases to evolve to handle:
- Massive scale data storage and processing
- Real-time data analysis
- Complex data relationships
- Integration with AI/ML systems