This post contains some reference notes for using both relational and non-relational databases as well as an overview of a project completed for the Applied Databases module as part of the Higher Diploma in Data Analytics at GMIT.

• MySQL is a relational database management system. Queries are written in the SQL language.
• MongoDb is a document database used for non-structured data. MongoDB is based on JSON.

The applied databases module provided a primer on databases with a focus on data analysis; CRUD ( Creation, Retrieval, Update and Deletion) of both structured and unstructured data for a number of modern database systems and architectures; Topics on Relational databases, NoSQL databases, databases interfaces and database logic.

The project for the Applied databases module had 4 different sections.

1. Working with a relational database using MySQL.
   Import the world.sql database and then write queries to satisfy some questions.

   • The MySQL ‘world’ database
     An overview of the World database used for the project. Importing the database and looking at the structure of the tables.
   • MySQL project queries on the World database
     Some MySQL queries for the project. This post contains just the question, query and result.
   • MySQl project queries in more details This post goes through the workings for the previous post.

 

2. Working with a non-relational ‘student / courses’ database using MongoDB
   Writing some queries to satisfy some questions on a student / courses database

   • The MongoDb Student and Courses database The database used for the project.

   • MongoDb Queries for the project

   • MongoDb Project Queries in more detail Questions for the project with the queries.

 

3. Writing a Python application that allows a user perform CRUD operations on both relational and non-relational databases. The application consists of a main menu with an interface to a MySQL database and a MongoDB database.

   • Python Interface to the MySQL database Python module for connecting to the MySQL database for the project using the pymysql module.
   • Python Interface to the MongoDB database:
     Python module for connecting to MongoDB to the proj20DB database using the pymongo module.
   • Python application: Main Menu
     Menu for the Python application to interface with both the MySQL database and the MongoDB database.
      

4. Normalisation: Examining a relational database to see whether it is considered a good or bad design. A discussion on the design of a sample database.

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MySQL: Some notes on Relational Databases

• Some notes on using MySQL
  MySQL is a database management system. Some notes on using MySQL using either the MySQLWorkbench application or using the command line interface. An overview and some examples of queries.

• Relational database tables
  An overview of relational databases, SQL, MySQL and common queries.

MongoDB: Some notes on Non-Relational Databases

• An overview of MongoDB
  Some notes on using MongoDb, JSON structure, common queries etc

• Some more notes on using MongoDb

• Some notes on Non-Relational Databases and using MongoDB.
  Some more notes on using MongoDb. There is some overlap with previous posts.

• MongoDB examples
  Install and running MongoDb as well as some example queries.

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