Introduction to Databases

As a senior backend engineer, you may have encountered situations where handling data efficiently and effectively is crucial. Databases play a fundamental role in managing and organizing large amounts of data. In this lesson, we will explore the theoretical concepts behind databases.

What is a database?

A database is simply a system that allows us to store and process data in an efficient manner. It provides a structured and organized way to store information, making it easier to retrieve and manipulate as needed.

Types of databases

There are various types of databases, each designed with specific use cases in mind. Some common types include:

• Relational databases
• NoSQL databases
• Graph databases
• Document databases

Relational databases

Relational databases are the most commonly used type of database. They are based on the relational model and use tables to store data. Each table consists of rows and columns, where each row represents a record and each column represents a specific attribute or field.

We can think of a relational database as a collection of interconnected spreadsheets, where each spreadsheet is a table and each row in the spreadsheet is a record.

NoSQL databases

NoSQL databases, on the other hand, are designed for handling unstructured or semi-structured data. They provide flexibility and scalability, allowing for rapid application changes and handling large amounts of data. Unlike relational databases, NoSQL databases do not require a fixed schema and can store data in a variety of formats, such as key-value pairs, documents, or graphs.

Conclusion

In this lesson, we have introduced the concept of databases and explored the differences between relational and NoSQL databases. Understanding these fundamental concepts will provide a solid foundation as we delve deeper into the world of databases and their implementation.

xxxxxxxxxx

if __name__ == "__main__":

  db = Database()

  db.connect()

  db.create_table('users')

​

  user = {

    'name': 'John',

    'age': 28,

    'email': 'john@example.com'

  }

​

  db.insert('users', user)

​

  result = db.select('users')

  print(result)