NoSQL: Cassandra Batch to execute multiple Statements

Anvesh Patel — Tue, 10 Jan 2017 19:42:37 +0000

In this post, I am sharing basic help to execute multiple statements using one single Cassandra batch.

Many times, it is required to execute multiple statements using single batch.
Cassandra CQL provides the BEGIN BATCH…APPLY BATCH command to execute multiple statements.

Below is a small demonstration:

Create Keyspace if not exists:

CREATE KEYSPACE IF NOT EXISTS dbrnd WITH replication = {'class': 'SimpleStrategy', 'replication_factor' : 3};

Use a Keyspace:

USE dbrnd;

Create a Sample Table:

CREATE TABLE IF NOT EXISTS tbl_Employee 
(
  EmpID INT PRIMARY KEY
  ,EmpFirstName VARCHAR
  ,EmpLastName VARCHAR
  ,EmpSalary INT
);

Insert few sample records:

INSERT INTO tbl_Employee 
(EmpID,EmpFirstName,EmpLastName,EmpSalary)
VALUES
(1,'Anvesh','Patel',50000);

INSERT INTO tbl_Employee 
(EmpID,EmpFirstName,EmpLastName,EmpSalary)
VALUES
(2,'Neevan','Patel',150000);

Execute INSERT, UPDATE, DELETE using one Single Batch command:

cassandra@cqlsh:dbrnd> 
    begin batch
         INSERT INTO tbl_Employee
         (EmpID,EmpFirstName,EmpLastName,EmpSalary)
         VALUES
         (3,'Meera','Patel',80000);
         UPDATE tbl_Employee SET EmpFirstName ='Martin' WHERE EmpID=2;
         
         DELETE FROM tbl_Employee WHERE EmpID=3;
    apply batch;

Check the result:

cassandra@cqlsh:dbrnd> SELECT *FROM tbl_Employee;

@ Row 1
--------------+--------
 empid        | 1
 empfirstname | Anvesh
 emplastname  | Patel
 empsalary    | 50000

@ Row 2
--------------+--------
 empid        | 2
 empfirstname | Martin
 emplastname  | Patel
 empsalary    | 150000

(2 rows)

apply batch – Database Research & Development

NoSQL: Cassandra Batch to execute multiple Statements