Find distinct values (Python)
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.
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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
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'}]Parameters
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 |
|---|---|---|
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The field for which to find values. See the examples for usage. |
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An object that defines filter criteria using the Data API filter syntax. The method only finds documents that match the filter criteria. Filters can improve performance by reducing the number of documents that the Data API processes. You must use For a list of available filter operators and more examples, see Filter operators for collections (Python). 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. For an example, see Find distinct values for a subset of documents. |
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Optional. The maximum time, in milliseconds, that the whole operation, which might 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 This parameter is aliased as |
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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 |
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
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)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.
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)Find distinct values of an index in an array
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)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 (Python).
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.
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)Client reference
For more information, see the client reference.
