To delete data from a table in Cassandra, the DELETE command is used.
Syntax:
DELETE FROM <identifier> WHERE <condition>; |
Example 1: Delete an entire row.
Employees table:
id name salary 1 Adi 50000 2 Bruno 30000 3 Chris 60000 4 Davis 20000 5 Eliza 15000
Query:
DELETE FROM employees WHERE id = 4; |
Explanation:
In the above example, we are deleting the row, where the value of ID is 4.
Verify it by using the below command.
SELECT * FROM employees;
Output:
id name salary 1 Adi 50000 2 Bruno 30000 3 Chris 60000 5 Eliza 15000
Example 2: Delete a specific value.
Employees table:
id name salary 1 Adi 50000 2 Bruno 30000 3 Chris 60000 4 Davis 20000 5 Eliza 15000
Query:
DELETE salary FROM employees WHERE ID = 3; |
Explanation:
In the above example, we are deleting the value of the ‘salary’ column, where the value of ID is 3.
Verify it by using the below command.
SELECT * FROM employees;
Output:
id name salary 1 Adi 50000 2 Bruno 30000 3 Chris null 4 Davis 20000 5 Eliza 15000