Create an index (Java)

Tables with the Data API are currently in public preview. Development is ongoing, and the features and functionality are subject to change. Hyper-Converged Database (HCD), and the use of such, is subject to the DataStax Preview Terms.

Creates a new index for a column in a table in a database.

You should index any column that you want to sort or filter on that isn’t part of the primary key. Columns that are part of the primary key do not require a secondary index.

To create an index on a vector column, see Create a vector index (Java) instead.

The username and password used to generate the token must be tied to a role that has sufficient permissions to perform the desired operations.

Ready to write code? See the examples for this method to get started. If you are new to the Data API, check out the quickstart.

Result

Creates an index for the specified column.

Does not return anything.

Parameters

Use the createIndex method, which belongs to the com.datastax.astra.client.tables.Table class.

Method signature 
void createIndex(
  String indexName,
  String columnName
)
void createIndex(
  String indexName,
  String columnName,
  CreateIndexOptions indexOptions
)
void createIndex(
  String indexName,
  TableIndexDefinition indexDefinition,
  CreateIndexOptions indexOptions
)
Name Type Summary

name

str

The name of the index.

Index names for tables must follow these rules:

  • Must be unique within the keyspace

  • Can contain letters, numbers, and underscores

  • Must have a length of 1 to 100 characters

definition

TableIndexDefinition

The index definition. See Methods of the TableIndexDefinition constructor for more details.

options

CreateIndexOptions

The options for this operation. See Methods of the CreateIndexOptions constructor for more details.
Methods of the TableIndexDefinition constructor
Method Type Summary

column()

string

The name of the table column on which to create the index.

You cannot create indexes based on map, list, or set columns.

To create vector indexes based on vector columns, see Create a vector index (Java).

options()

TableIndexDefinitionOptions

Optional. Specifies index options for text and ASCII types.

For examples, see Create an index and specify ASCII conversion before indexing, Create an index and specify Unicode normalization, and Create an index and specify case sensitivity.
Methods of the CreateIndexOptions constructor
Method Type Summary

ifNotExists()

boolean

Optional. Whether the command should silently succeed even if an index with the given name already exists in the keyspace and no new index was created.

This option only checks index names. It does not check index definitions.

For an example, see Create an index only if the index does not exist.

Default: false

Examples

The following examples demonstrate how to create an index.

Create an index

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.definition.rows.Row;

public class Example {

  public static void main(String[] args) {
    // Get an existing table
    Table<Row> table =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getTable("TABLE_NAME");

    // Index a column
    table.createIndex("INDEX_NAME", "COLUMN_NAME");
  }
}

Create an index and specify ASCII conversion before indexing

When you index a text or ASCII column, you can specify whether to convert non-ASCII characters to their US-ASCII equivalent before indexing.

Converting non-ASCII characters can improve search performance by limiting the range of allowed ASCII characters. This option is best for ASCII-only data or ASCII-only applications where you can safely ignore non-ASCII characters. It is not recommended for multilingual data or applications that must support non-ASCII characters.

For more information, see Index options for text and ASCII types.

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.options.CreateIndexOptions;
import com.datastax.astra.client.tables.definition.indexes.TableIndexDefinitionOptions;
import com.datastax.astra.client.tables.definition.indexes.TableRegularIndexDefinition;
import com.datastax.astra.client.tables.definition.rows.Row;

public class Example {

  public static void main(String[] args) {
    // Get an existing table
    Table<Row> table =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getTable("TABLE_NAME");

    // Index a column
    TableRegularIndexDefinition definition =
        new TableRegularIndexDefinition()
            .column("COLUMN_NAME")
            .options(new TableIndexDefinitionOptions().ascii(true));

    CreateIndexOptions options = new CreateIndexOptions();
    table.createIndex("INDEX_NAME", definition, options);
  }
}

Create an index and specify Unicode normalization

When you index a text or ASCII column, you can specify whether to normalize Unicode characters and diacritics before indexing.

Normalizing Unicode characters can improve search consistency and inclusivity. This option is best for datasets that can contain multiple Unicode versions of the same character, such as multilingual data or non-standardized user input.

For more information, see Index options for text and ASCII types.

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.options.CreateIndexOptions;
import com.datastax.astra.client.tables.definition.indexes.TableIndexDefinitionOptions;
import com.datastax.astra.client.tables.definition.indexes.TableRegularIndexDefinition;
import com.datastax.astra.client.tables.definition.rows.Row;

public class Example {

  public static void main(String[] args) {
    // Get an existing table
    Table<Row> table =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getTable("TABLE_NAME");

    // Index a column
    TableRegularIndexDefinition definition =
        new TableRegularIndexDefinition()
            .column("COLUMN_NAME")
            .options(new TableIndexDefinitionOptions().normalize(true));

    CreateIndexOptions options = new CreateIndexOptions();
    table.createIndex("INDEX_NAME", definition, options);
  }
}

Create an index and specify case sensitivity

When you index a text or ASCII column, you can specify whether the index is case sensitive.

Enforcing case sensitivity is best for datasets where you want to enforce exact matches based on capitalization.

For more information, see Index options for text and ASCII types.

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.options.CreateIndexOptions;
import com.datastax.astra.client.tables.definition.indexes.TableIndexDefinitionOptions;
import com.datastax.astra.client.tables.definition.indexes.TableRegularIndexDefinition;
import com.datastax.astra.client.tables.definition.rows.Row;

public class Example {

  public static void main(String[] args) {
    // Get an existing table
    Table<Row> table =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getTable("TABLE_NAME");

    // Index a column
    TableRegularIndexDefinition definition =
        new TableRegularIndexDefinition()
            .column("COLUMN_NAME")
            .options(new TableIndexDefinitionOptions().caseSensitive(false));

    CreateIndexOptions options = new CreateIndexOptions();
    table.createIndex("INDEX_NAME", definition, options);
  }
}

Create an index only if the index does not exist

Use this option to silently do nothing if an index with the specified name already exists.

This option only checks index names. It doesn’t check the type or content of any existing indexes.

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.options.CreateIndexOptions;
import com.datastax.astra.client.tables.definition.rows.Row;

public class Example {

  public static void main(String[] args) {
    // Get an existing table
    Table<Row> table =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getTable("TABLE_NAME");

    // Index a column
    CreateIndexOptions options = new CreateIndexOptions().ifNotExists(true);
    table.createIndex("INDEX_NAME", "COLUMN_NAME", options);
  }
}

Client reference

For more information, see the client reference.

Was this helpful?

Give Feedback

How can we improve the documentation?

© Copyright IBM Corporation 2026 | Privacy policy | Terms of use |  Manage Privacy Choices

Apache, Apache Cassandra, Cassandra, Apache Tomcat, Tomcat, Apache Lucene, Apache Solr, Apache Hadoop, Hadoop, Apache Pulsar, Pulsar, Apache Spark, Spark, Apache TinkerPop, TinkerPop, Apache Kafka and Kafka are either registered trademarks or trademarks of the Apache Software Foundation or its subsidiaries in Canada, the United States and/or other countries. Kubernetes is the registered trademark of the Linux Foundation.

General Inquiries: Contact IBM