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.

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

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 as a Set. 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 extract the desired values from the response.

Parameters

Python
TypeScript
Java
curl

Use the distinct method, which belongs to the astrapy.Collection class.

Method signature

distinct(
  key: str | Iterable[str | int],
  *,
  filter: Dict[str, Any],
  general_method_timeout_ms: int,
  request_timeout_ms: int,
  timeout_ms: int,
) -> list[Any]

Name Type Summary

Name	Type	Summary
`key`	`str \| Iterable[str \| int]`	The field for which to find values. See Examples for usage.
`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 Filter operators for collections. Filters can use only indexed fields. If you apply selective indexing when you create a collection, you cannot reference non-indexed fields in a filter.
`general_method_timeout_ms`	`int`	Optional. The maximum time, in milliseconds, that the whole operation, which may involve multiple HTTP requests, can take. Default: The default value for the collection. This default is 30 seconds unless you specified a different default when you initialized the `Collection` or `DataAPIClient` object. For more information, see Timeout options. This parameter is aliased as `timeout_ms` for convenience.
`request_timeout_ms`	`int`	Optional. The maximum time, in milliseconds, that the client should wait for each underlying HTTP request. Default: The default value for the collection. This default is 10 seconds unless you specified a different default when you initialized the `Collection` object. For more information, see Timeout options.

key

str | Iterable[str | int]

The field for which to find values.

See Examples for usage.

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 Filter operators for collections.

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

general_method_timeout_ms

int

Optional. The maximum time, in milliseconds, that the whole operation, which may involve multiple HTTP requests, can take.

Default: The default value for the collection. This default is 30 seconds unless you specified a different default when you initialized the Collection or DataAPIClient object. For more information, see Timeout options.

This parameter is aliased as timeout_ms for convenience.

request_timeout_ms

int

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

Default: The default value for the collection. This default is 10 seconds unless you specified a different default when you initialized the Collection object. For more information, see Timeout options.

Use the distinct method, which belongs to the Collection class.

Method signature

async distinct(
  key: Key,
  filter: CollectionFilter<Schema>,
  options: {
    timeout?: number | TimeoutDescriptor,
  },
): Flatten<(SomeDoc & ToDotNotation<Schema>)[Key]>[]

Name Type Summary

Name	Type	Summary
`key`	`string`	The name of the field for which to find values. See Examples for usage.
`filter`	`CollectionFilter<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 Filter operators for collections. Filters can use only indexed fields. If you apply selective indexing when you create a collection, you cannot reference non-indexed fields in a filter.
`options`	`object`	Optional. The options for this operation. See Properties of `options` for more details.

key

string

The name of the field for which to find values.

See Examples for usage.

filter

CollectionFilter<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 Filter operators for collections.

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

options

object

Optional. The options for this operation. See Properties of options for more details.

Properties of `options`
Name	Type	Summary
`timeout`	`number` \| `TimeoutDescriptor`	Optional. The timeout(s) to apply to this method. You can specify `requestTimeoutMs` and `generalMethodTimeoutMs`. Since this method issues a single HTTP request, these timeouts are equivalent. Details about the `timeout` parameter The `TimeoutDescriptor` object can contain these properties: `requestTimeoutMs` (`number`): The maximum time, in milliseconds, that the client should wait for each underlying HTTP request. Default: The default value for the collection. This default is 10 seconds unless you specified a different default when you initialized the `Collection` or `DataAPIClient` object. `generalMethodTimeoutMs` (`number`): The maximum time, in milliseconds, that the whole operation can take. Since this method issues a single HTTP request, `generalMethodTimeoutMs` and `requestTimeoutMs` are equivalent. If you specify both, the minimum of the two will be used. Default: The default value for the collection. This default is 30 seconds unless you specified a different default when you initialized the `Collection` or `DataAPIClient` object. If you specify a number instead of a `TimeoutDescriptor` object, that number will be applied to both `requestTimeoutMs` and `generalMethodTimeoutMs`.

Use the distinct method, which belongs to the com.datastax.astra.client.Collection class.

Method signature

<R> Set<R> distinct(
  String key,
  Class<F> resultClass
)

<R> Set<R> distinct(
  String key,
  Filter filter,
  Class<F> resultClass
)

Name Type Summary

Name	Type	Summary
`key`	`String`	The name of the field for which to find values.
`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 Filter operators for collections. Filters can use only indexed fields. If you apply selective indexing when you create a collection, you cannot reference non-indexed fields in a filter.
`resultClass`	`Class`	The type of the values that you expect this method to return.

key

String

The name of the field for which to find values.

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 Filter operators for collections.

Filters can use only indexed fields. If you apply selective indexing when you create a collection, you cannot 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 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()
database = client.get_database(
    "API_ENDPOINT",
    token="APPLICATION_TOKEN",
)
collection = database.get_collection("COLLECTION_NAME")

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

print(result)

import { DataAPIClient } from "@datastax/astra-db-ts";

// Get an existing collection
const client = new DataAPIClient("APPLICATION_TOKEN");
const database = client.db("API_ENDPOINT");
const collection = database.collection("COLLECTION_NAME");

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

  console.log(result);
})();

import com.datastax.astra.client.DataAPIClient;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import java.util.Set;

public class Example {

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

    // Find distinct values
    Set<String> result = collection.distinct("author", 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 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.

You must use & to escape any literal . or & in field names.

Python
TypeScript
Java
curl

from astrapy import DataAPIClient

# Get an existing collection
client = DataAPIClient()
database = client.get_database(
    "API_ENDPOINT",
    token="APPLICATION_TOKEN",
)
collection = database.get_collection("COLLECTION_NAME")

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

Alternatively, you can use an array to denote nested fields:

from astrapy import DataAPIClient

# Get an existing collection
client = DataAPIClient()
database = client.get_database(
    "API_ENDPOINT",
    token="APPLICATION_TOKEN",
)
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("APPLICATION_TOKEN");
const database = client.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 extract the desired values from the response.

Find distinct values of an index in an array

Python
TypeScript
Java
curl

To find distinct values for a specific index in an array, specify the field name and index as an array. For example, ["genres", 0] finds distinct values of the first position of an array stored in the "genres" field.

The index should be an integer, not a string. For example, ["genres", "0"] matches {"genres": {"0": <value>}} but not {"genres": [<value>, …]}.

If you use use the index in a string with dot notation instead of array notation, the method matches both maps and arrays. For example field_name.0 matches {"field_name": {"0": <value>}} and {"field_name": [<value>, …]}.

If an array is encountered and no numeric index is specified, the method visits all items in the array.

from astrapy import DataAPIClient

# Get an existing collection
client = DataAPIClient()
database = client.get_database(
    "API_ENDPOINT",
    token="APPLICATION_TOKEN",
)
collection = database.get_collection("COLLECTION_NAME")

# Find distinct values
result = collection.distinct(["genres", 2])
print(result)

To find distinct values for a specific index in an array, specify the index with dot notation. For example, genres.0 finds distinct values of the first position of an array stored in the "genres" field.

If an array is encountered and no numeric index is specified, the method visits all items in the array.

import { DataAPIClient } from "@datastax/astra-db-ts";

// Get an existing collection
const client = new DataAPIClient("APPLICATION_TOKEN");
const database = client.db("API_ENDPOINT");
const collection = database.collection("COLLECTION_NAME");

(async function () {
  // Find distinct values
  const result = await collection.distinct("genres.2", {});

  console.log(result);
})();

The Java client does not support dot notation or array notation to find distinct values for a specific index in an array.

This method has no literal equivalent in HTTP. Instead, you can use Find documents, and then 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 Filter operators for collections.

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

Python
TypeScript
Java
curl

from astrapy import DataAPIClient

# Get an existing collection
client = DataAPIClient()
database = client.get_database(
    "API_ENDPOINT",
    token="APPLICATION_TOKEN",
)
collection = database.get_collection("COLLECTION_NAME")

# Find distinct values
result = collection.distinct(
    "publication_year",
    filter={
        "$and": [
            {"is_checked_out": False},
            {"number_of_pages": {"$lt": 300}},
        ]
    },
)

print(result)

import { DataAPIClient } from "@datastax/astra-db-ts";

// Get an existing collection
const client = new DataAPIClient("APPLICATION_TOKEN");
const database = client.db("API_ENDPOINT");
const collection = database.collection("COLLECTION_NAME");

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

  console.log(result);
})();

import com.datastax.astra.client.DataAPIClient;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Set;

public class Example {

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

    // Find distinct values
    Filter filter =
        Filters.and(Filters.eq("is_checked_out", false), Filters.lt("number_of_pages", 300));
    Set<String> result = collection.distinct("author", 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 extract the desired values from the response.

Client reference

Python
TypeScript
Java
curl

For more information, see the client reference.

Client reference documentation is not applicable for HTTP.

Find distinct values

Result

Parameters

Examples

Find distinct values of a top level field

Find distinct values of a nested field

Find distinct values of an index in an array

Find distinct values for a subset of documents

Client reference

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