Cassandra Drop Index - Apache Cassandra

What is Cassandra Drop Index?

Dropping an Index using Cqlsh

You can drop an index using the command DROP INDEX. Its syntax is as follows:

Given below is an example to drop an index of a column in a table. Here we are dropping the index of the column name in the table emp.

Dropping an Index using Java API

You can drop an index of a table using the execute() method of Session class. Follow the steps given below to drop an index from a table.

Step1: Create a Cluster Object

Create an instance of Cluster.builder class of com.datastax.driver.core package as shown below.

Add a contact point (IP address of the node) using the addContactPoint() method of Cluster.Builder object. This method returns Cluster.Builder.

Using the new builder object, create a cluster object. To do so, you have a method called build() in the Cluster.Builder class. The following code shows how to create a cluster object.

You can build a cluster object using a single line of code as shown below.

Step 2: Create a Session Object

Create an instance of Session object using the connect() method of Cluster class as shown below.

This method creates a new session and initializes it. If you already have a keyspace, then you can set it to the existing one by passing the KeySpace name in string format to this method as shown below.

Here we are using the KeySpace named tp. Therefore, create the session object as shown below.

Step 3: Execute Query

You can execute CQL queries using the execute() method of Session class. Pass the query either in string format or as a Statement class object to the execute() method. Whatever you pass to this method in string format will be executed on the cqlsh.

In the following example, we are dropping an index “name” of emp table. You have to store the query in a string variable and pass it to the execute() method as shown below.

Given below is the complete program to drop an index in Cassandra using Java API.

Save the above program with the class name followed by .java, browse to the location where it is saved. Compile and execute the program as shown below.

Under normal conditions, it should produce the following output:

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