Find distinct values

Finds the distinct values of a key for documents in a collection.

This method finds all documents that match the filter, or all documents if no filter is applied. There can be performance, latency, and billing implications if there are many matching documents.

Method signature

  • Python

  • TypeScript

  • Java

  • curl

collection.distinct(
    key: str,
    *,
    filter: Dict[str, Any],
    max_time_ms: int,
) -> list[Any]
collection.distinct(
  key: Key,
  filter: Filter<Schema>,
): Promise<Flatten<(SomeDoc & ToDotNotation<FoundDoc<Schema>>)[Key]>[]>
<F> DistinctIterable<T, F> distinct(
  String key,
  Class<F> resultClass
)
<F> DistinctIterable<T, F> distinct(
  String key,
  Filter filter,
  Class<F> resultClass
)

This method has no literal equivalent in HTTP. Instead, you can use Find documents, and then use jq or another utility to extract the desired values from the response.

Result

  • Python

  • TypeScript

  • Java

  • curl

Returns a list of the distinct values of the specified key. The method excludes documents that do not include the requested key.

Example response:

['home_appliance', None, 'sports_equipment', {'cat_id': 54, 'cat_name': 'gardening_gear'}]

Returns a promise that resolves to a list of the distinct values of the specified key. Documents that do not include the requested key are ignored.

The TypeScript client will attempt to infer the return type. However, you may need to explicitly cast the return type to match the expected type.

Example resolved response:

['home_appliance', None, 'sports_equipment', {'cat_id': 54, 'cat_name': 'gardening_gear'}]

Returns a list of the distinct values of the specified key (DistinctIterable<F>). Documents that do not include the requested key are ignored.

This method has no literal equivalent in HTTP. Instead, you can use Find documents, and then use jq or another utility to extract the desired values from the response.

Parameters

  • Python

  • TypeScript

  • Java

  • curl

Name Type Summary

key

str

The name of the field for which to find values.

To find distinct values for a nested field, use dot notation. For example, field.subfield.subsubfield.

To use dot notation for a list, specify a numeric index. For example, field.3. If a list is encountered and no numeric index is specified, the method visits all items in the list.

filter

Dict[str, Any]

An object that defines filter criteria using the Data API filter syntax. The method only finds documents that match the filter criteria.

For a list of available filter operators and more examples, see Data API operators.

Filters can use only indexed fields. If you apply selective indexing when you create a collection, you can’t reference non-indexed fields in a filter.

max_time_ms

int

Optional. The maximum time, in milliseconds, that the client should wait for the underlying HTTP request.

Default: The default value for the collection. This default is 30 seconds unless you specified a different default when you initialized the Collection object.
Name Type Summary

key

string

The name of the field for which to find values.

To find distinct values for a nested field, use dot notation. For example, field.subfield.subsubfield.

To use dot notation for a list, specify a numeric index. For example, field.3. If a list is encountered and no numeric index is specified, the method visits all items in the list.

filter

Filter<Schema>

An object that defines filter criteria using the Data API filter syntax. The method only finds documents that match the filter criteria.

For a list of available filter operators and more examples, see Data API operators.

Filters can use only indexed fields. If you apply selective indexing when you create a collection, you can’t reference non-indexed fields in a filter.
Name Type Summary

key

String

The name of the field for which to find values.

The Java client does not support dot notation to find distinct values for nested fields.

filter

Filter

An object that defines filter criteria using the Data API filter syntax. The method only finds documents that match the filter criteria.

For a list of available filter operators and more examples, see Data API operators.

Filters can use only indexed fields. If you apply selective indexing when you create a collection, you can’t reference non-indexed fields in a filter.

resultClass

Class

The type of the values that you expect this method to return.

This method has no literal equivalent in HTTP. Instead, you can use Find documents, and then use jq or another utility to extract the desired values from the response.

Examples

The following examples demonstrate how to find distinct values of a key for documents in a collection.

Find distinct values of a top level field

  • Python

  • TypeScript

  • Java

  • curl

from astrapy import DataAPIClient

# Get an existing collection
client = DataAPIClient("ASTRA_DB_APPLICATION_TOKEN")
database = client.get_database("ASTRA_DB_API_ENDPOINT")
collection = database.get_collection("COLLECTION_NAME")

# Find distinct values
result = collection.distinct("publicationYear")

print(result)
import { DataAPIClient } from '@datastax/astra-db-ts';

// Get an existing collection
const client = new DataAPIClient('ASTRA_DB_APPLICATION_TOKEN');
const database = client.db('ASTRA_DB_API_ENDPOINT');
const collection = database.collection('COLLECTION_NAME');

(async function () {
  // Find distinct values
  const result = await collection.distinct("publicationYear");

  console.log(result)
})();
package com.datastax.astra.client.collection;

import com.datastax.astra.client.Collection;
import com.datastax.astra.client.DataAPIClient;
import com.datastax.astra.client.model.Document;
import com.datastax.astra.client.model.Filter;
import com.datastax.astra.client.model.Filters;
import com.datastax.astra.client.model.DistinctIterable;

public class FindDistinct {

    public static void main(String[] args) {
        // Get an existing collection
        Collection<Document> collection = new DataAPIClient("ASTRA_DB_APPLICATION_TOKEN")
            .getDatabase("ASTRA_DB_API_ENDPOINT")
            .getCollection("COLLECTION_NAME");

        // Find distinct values
        DistinctIterable<Document, String> result = collection
                .distinct("publicationYear", String.class);

        for (String fieldValue : result) {
            System.out.println(fieldValue);
        }
    }
}

This method has no literal equivalent in HTTP. Instead, you can use Find documents, and then use jq or another utility to extract the desired values from the response.

Find distinct values of a nested field

To find distinct values for a nested field, use dot notation. For example, field.subfield.subsubfield.

To use dot notation for a list, specify a numeric index. For example, field.3. If a list is encountered and no numeric index is specified, the method visits all items in the list.

  • Python

  • TypeScript

  • Java

  • curl

from astrapy import DataAPIClient

# Get an existing collection
client = DataAPIClient("ASTRA_DB_APPLICATION_TOKEN")
database = client.get_database("ASTRA_DB_API_ENDPOINT")
collection = database.get_collection("COLLECTION_NAME")

# Find distinct values
result = collection.distinct("metadata.language")

print(result)
import { DataAPIClient } from '@datastax/astra-db-ts';

// Get an existing collection
const client = new DataAPIClient('ASTRA_DB_APPLICATION_TOKEN');
const database = client.db('ASTRA_DB_API_ENDPOINT');
const collection = database.collection('COLLECTION_NAME');

(async function () {
  // Find distinct values
  const result = await collection.distinct("metadata.language");

  console.log(result)
})();

The Java client does not support dot notation to find distinct values for nested fields.

This method has no literal equivalent in HTTP. Instead, you can use Find documents, and then use jq or another utility to extract the desired values from the response.

Find distinct values for a subset of documents

You can use a filter to find distinct values across documents that match the filter.

For a list of available filter operators and more examples, see Data API operators.

Filters can use only indexed fields. If you apply selective indexing when you create a collection, you can’t reference non-indexed fields in a filter.

  • Python

  • TypeScript

  • Java

  • curl

from astrapy import DataAPIClient

# Get an existing collection
client = DataAPIClient("ASTRA_DB_APPLICATION_TOKEN")
database = client.get_database("ASTRA_DB_API_ENDPOINT")
collection = database.get_collection("COLLECTION_NAME")

# Find distinct values
result = collection.distinct(
  "publicationYear",
  filter={
    "$and": [
      {"isCheckedOut": False},
      {"numberOfPages": {"$lt": 300}},
    ]
  }
)

print(result)
import { DataAPIClient } from '@datastax/astra-db-ts';

// Get an existing collection
const client = new DataAPIClient('ASTRA_DB_APPLICATION_TOKEN');
const database = client.db('ASTRA_DB_API_ENDPOINT');
const collection = database.collection('COLLECTION_NAME');

(async function () {
  // Find distinct values
  const result = await collection.distinct(
    "publicationYear",
    {
      "$and": [
        {"isCheckedOut": false},
        {"numberOfPages": {"$lt": 300}},
      ]
    }
  );

  console.log(result)
})();
package com.datastax.astra.client.collection;

import com.datastax.astra.client.Collection;
import com.datastax.astra.client.DataAPIClient;
import com.datastax.astra.client.model.Document;
import com.datastax.astra.client.model.Filter;
import com.datastax.astra.client.model.Filters;
import com.datastax.astra.client.model.DistinctIterable;

public class FindDistinct {

    public static void main(String[] args) {
        // Get an existing collection
        Collection<Document> collection = new DataAPIClient("ASTRA_DB_APPLICATION_TOKEN")
            .getDatabase("ASTRA_DB_API_ENDPOINT")
            .getCollection("COLLECTION_NAME");

        // Find distinct values
        Filter filter = Filters.and(
          Filters.eq("isCheckedOut", false),
          Filters.lt("numberOfPages", 300));
        DistinctIterable<Document, String> result = collection
                .distinct("publicationYear", filter, String.class);

        for (String fieldValue : result) {
            System.out.println(fieldValue);
        }
    }
}

This method has no literal equivalent in HTTP. Instead, you can use Find documents, and then use jq or another utility to extract the desired values from the response.

Client reference

  • Python

  • TypeScript

  • Java

  • curl

For more information, see the client reference.

For more information, see the client reference.

For more information, see the client reference.

Client reference documentation is not applicable for HTTP.

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