Cassandra Tutorial

Cassandra is a distributed database management system designed to handle large amounts of data across many commodity servers, providing high availability with no single point of failure. Cassandra is open source and is used by many companies including Netflix, eBay, and Twitter.

Syntax

The syntax for creating a table in Cassandra is as follows:

CREATE TABLE table_name (
    column_name data_type PRIMARY KEY,
    column_name data_type,
    column_name data_type
);

Example

Let's create a table in Cassandra called users with the following columns:

• id (UUID, primary key)
• username (text)
• email (text)
• age (int)

CREATE TABLE users (
    id uuid PRIMARY KEY,
    username text,
    email text,
    age int
);

Output

The output of the above example is a new table called users with the specified columns.

Explanation

In Cassandra, data is stored in tables. Each table consists of rows (also called records or tuples) and columns (also call fields or attributes). A column family in Cassandra corresponds to a table in a relational database.

The CREATE TABLE statement is used to create a new table in Cassandra. In the example, the users table is created with four columns: id, username, email, and age. The id column is the primary key, which means it uniquely identifies each row in the table. The uuid data type is used to generate a unique id for each row.

Use

Cassandra can be used when handling large amounts of structured and semi-structured data across different data centers and geographic locations. It is useful in situations where high availability and scalability are important. Cassandra is commonly used in applications that require real-time data management and analytics, such as e-commerce, social media, and gaming.

Important Points

• Cassandra is a distributed database management system that provides high availability with no single point of failure.
• Data is stored in tables, which consist of rows and columns.
• A column family in Cassandra corresponds to a table in a relational database.
• The CREATE TABLE statement is used to create a new table in Cassandra with specified columns.
• The primary key uniquely identifies each row in a table.
• Cassandra supports CQL (Cassandra Query Language) for querying data and managing the database.

Summary

In this tutorial, we learned about Cassandra, its syntax for creating tables, and its primary use cases. Cassandra is a distributed database management system that is commonly used in applications that require high availability and scalability. It is designed to handle large amounts of structured and semi-structured data across different data centers and geographic locations. Cassandra's flexibility and scalability make it a popular choice for handling big data.