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Cassandra Batch

We can execute multiple modification statements simultaneously in Cassandra, whether it is an insert, update or delete statement.
Syntax:

BEGIN BATCH  
<insert-stmt>/ <update-stmt>/ <delete-stmt>  
APPLY BATCH

Example:
Employees table:

id	name	salary
1	Adi	50000
2	Bruno	30000
3	Chris	60000
4	Davis	20000
5	Eliza	15000

Query:

BEGIN BATCH
INSERT INTO employees<id, name, salary> 
values<6, 'Tom', 40000>;
UPDATE employees SET salary = 20000 WHERE ID = 2;
DELETE salary FROM employees WHERE ID = 3;
APPLY BATCH;

Explanation:
In the above example, we are inserting a new row in the ’employees’ table with the values: 6, Tom and 40000 in the respective columns. Next, we are updating the value of the ‘salary’ column to 20000, where the value of ID is 2. And at last, 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	20000
3	Chris	null
4	Davis	20000
5	Eliza	15000
6	Tom	40000
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