Apache Cassandra Cheatsheet #

Apache Cassandra is a distributed NoSQL database designed to handle large amounts of data across many commodity servers, providing high availability with no single point of failure.

General Commands #

Command/Option	Example	Description
`cqlsh`	`cqlsh`	Start the Cassandra Query Language shell
`DESCRIBE KEYSPACES;`	`DESCRIBE KEYSPACES;`	List all keyspaces
`DESCRIBE TABLE <table_name>;`	`DESCRIBE TABLE users;`	Describe a specific table
`SHOW TABLES;`	`SHOW TABLES;`	List all tables in the current keyspace

Keyspace and Table Management #

Command/Option	Example	Description
`CREATE KEYSPACE`	`CREATE KEYSPACE my_keyspace WITH REPLICATION = { 'class': 'SimpleStrategy', 'replication_factor': 3 };`	Create a new keyspace
`USE <keyspace>;`	`USE my_keyspace;`	Switch to a specific keyspace
`CREATE TABLE`	`CREATE TABLE users (id UUID PRIMARY KEY, name TEXT, age INT);`	Create a new table
`DROP TABLE`	`DROP TABLE users;`	Drop a table
`DROP KEYSPACE`	`DROP KEYSPACE my_keyspace;`	Drop a keyspace

CRUD Operations #

Command/Option	Example	Description
`INSERT INTO`	`INSERT INTO users (id, name, age) VALUES (uuid(), 'Alice', 30);`	Insert a new record
`SELECT`	`SELECT * FROM users;`	Query records from a table
`UPDATE`	`UPDATE users SET age = 31 WHERE name = 'Alice';`	Update a record
`DELETE`	`DELETE FROM users WHERE name = 'Alice';`	Delete a record

Indexes and Query Optimization #

Command/Option	Example	Description
`CREATE INDEX`	`CREATE INDEX ON users (age);`	Create an index on a column
`DROP INDEX`	`DROP INDEX users_age_idx;`	Drop an index
`ANALYZE TABLE`	`ANALYZE TABLE users;`	Analyze a table for query optimization

Data Import and Export #

Command/Option	Example	Description
`COPY FROM`	`COPY users (id, name, age) FROM 'users.csv' WITH DELIMITER = ',';`	Import data from a CSV file
`COPY TO`	`COPY users TO 'users.csv' WITH DELIMITER = ',';`	Export data to a CSV file

Cluster Management #

Command/Option	Example	Description
`nodetool status`	`nodetool status`	Check the status of the cluster
`nodetool repair`	`nodetool repair`	Repair inconsistencies in the cluster
`nodetool flush`	`nodetool flush`	Flush memtables to SSTables
`nodetool compact`	`nodetool compact`	Compact SSTables

Backup and Restore #

Command/Option	Example	Description
`nodetool snapshot`	`nodetool snapshot -t snapshot_name my_keyspace`	Create a snapshot backup
`sstableloader`	`sstableloader -d localhost:9042 /path/to/sstable`	Load SSTables into Cassandra

This cheatsheet provides essential Apache Cassandra commands and options for managing keyspaces, tables, and data, as well as performing backups and maintaining cluster health.