Find and replace a document (Python)

Finds a single document in a collection using filter and sort clauses, and then replaces that document. Optionally, if no document matches the filter, inserts a new document.

This method and the method to replace a document have the same database effect but differ in their return value. This method returns the document that was found and replaced. The method to replace a document returns details about the operation.

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

Replaces a document that matches the specified parameters, and returns a dictionary representation of the document. If no document was found, returns None.

The method parameters control whether the returned document reflects the original or updated values.

The fields included in the returned document depend on the projection specified in the method.

If an upsert is requested, the method inserts a new document if no document matches the filter.

Example response:

{'_id': 101, 'name': 'John Doe'}

Parameters

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

Method signature 
find_one_and_replace(
  filter: Dict[str, Any],
  replacement: Dict[str, Any],
  *,
  projection: Dict[str, bool],
  sort: Dict[str, Any],
  upsert: bool,
  return_document: str,
  general_method_timeout_ms: int,
  request_timeout_ms: int,
  timeout_ms: int,
) -> Dict[str, Any]
Name Type Summary

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. Filters can improve performance by reducing the number of documents that the Data API processes.

You must use & to escape any . or & in field names in the filter clause. You cannot use & to escape any other characters. For more information, see Work with . and & in field names (Python).

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 Replace a document that matches a filter.

replacement

Dict[str, Any]

An object describing the replacement document.

The replacement document should not include _id. The _id of the replaced document will be retained.

Field names in the replacement document must follow the same rules as when inserting a document.

See the examples for usage.

projection

Dict[str, bool]

Optional. Controls which fields are included or excluded in the returned document.

You must use & to escape any . or & in field names in the projection clause. You cannot use & to escape any other characters. For more information, see Work with . and & in field names (Python).

For more information, see Projections for collections (Python).

Default: The default projection for the collection. All fields prefixed with $ are excluded by default and will only be returned if you include them in the projection. _id is included by default and will always be returned unless you exclude it from the projection.

For examples, see Include only specific fields in the response and Exclude specific fields from the response.

sort

Dict[str, Any]

Optional. Sorts documents by one or more fields, or performs a vector search.

You must use & to escape any . or & in field names in the sort clause. You cannot use & to escape any other characters. For more information, see Work with . and & in field names (Python).

For more information, see Sort clauses for collections (Python).

Sort clauses can use only indexed fields. If you apply selective indexing when you create a collection, you cannot reference non-indexed fields in sort queries.

For vector searches, this parameter can use $vector.

For examples, see Replace a document after applying a non-vector sort and Replace a document that is most similar to a search vector.

upsert

bool

Optional. Whether to insert a new document if no document matches the filter criteria.

For an example, see Insert a new document if no matching document exists.

Default: False

return_document

str

Optional. Controls whether the response reflects the document before or after the replacement.

Can be one of:

For an example, see Include the new document in the response.

Default: ReturnDocument.BEFORE

general_method_timeout_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 or DataAPIClient object. For more information, see Timeout options.

request_timeout_ms

int

Optional. An alias for general_method_timeout_ms. Since this method issues a single HTTP request, general_method_timeout_ms and request_timeout_ms are equivalent.

timeout_ms

int

Optional. An alias for general_method_timeout_ms.

Examples

The following examples demonstrate how to replace a document in a collection.

Replace a document by ID

All documents have a unique _id property. You can use a filter to find a document with a specific _id, and then replace that document.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Replace a document
result = collection.find_one_and_replace(
    {"_id": "101"}, {"name": "Jane Doe", "age": 42}
)

print(result)

Replace a document that matches a filter

You can use a filter to find a document that matches specific criteria. For example, you can find a document with an is_checked_out value of false and a number_of_pages value less than 300.

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.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Replace a document
result = collection.find_one_and_replace(
    {
        "$and": [
            {"is_checked_out": False},
            {"number_of_pages": {"$lt": 300}},
        ]
    },
    {"is_checked_out": True, "borrower": "Brook Reed"},
)

print(result)

Replace a document that is most similar to a search vector

To find the document whose $vector value is most similar to a given vector, use a sort with the vector embeddings that you want to match. For more information, see Find data with vector search.

Vector search is only available for vector-enabled collections. For more information, see Create a collection that can store vector embeddings and $vector in collections (Python).

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Replace a document
result = collection.find_one_and_replace(
    {},
    {"name": "Jane Doe", "age": 42},
    sort={"$vector": [0.08, -0.62, 0.39]},
)

print(result)

Replace a document based on lexicographical matching

Lexicographical matching is 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.

There are two ways to use lexicographical matching to find documents with the Data API:

You can use these strategies together or separately.

You can only use lexicographical matching on collections that have lexical enabled. For more information, see Create a collection that supports lexicographical matching.

Documents must have the $lexical field populated to be included in lexicographical matching. For examples, see Insert a document for retrieval with lexicographical matching and Insert documents for retrieval with lexicographical matching.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Find and replace a document
result = collection.find_one_and_replace(
    {"$lexical": {"$match": "tree hill"}},
    {"is_checked_out": True, "borrower": "Brook Reed"},
    sort={"$lexical": "tree hill grassy"},
)

print(result)

Replace a document after applying a non-vector sort

You can use a sort clause to sort documents by one or more fields.

For more information, see Sort clauses for collections (Python).

Sort clauses can use only indexed fields. If you apply selective indexing when you create a collection, you cannot reference non-indexed fields in sort queries.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment, SortMode

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Replace a document
result = collection.find_one_and_replace(
    {"metadata.language": "English"},
    {"is_checked_out": False, "number_of_pages": 400},
    sort={
        "rating": SortMode.ASCENDING,
        "title": SortMode.DESCENDING,
    },
)

print(result)

Use nested fields in the replacement document

Although you can use dot notation in the filter to find a document, you cannot use dot notation in the replacement document. To specify nested fields in the replacement document, you must build a map, list, or set.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Replace a document
result = collection.find_one_and_replace(
    {"metadata.language": "English"},
    {
        "title": "Hidden Shadows of the Past",
        "number_of_pages": 481,
        "genres": ["Biography", "Graphic Novel", "Dystopian", "Drama"],
        "metadata": {
            "isbn": "978-1-905585-40-3",
            "language": "French",
            "edition": "Anniversary Edition",
        },
    },
)

print(result)

Use vector embeddings in the replacement document

Use the reserved $vector field to insert a document with pregenerated vector embeddings.

Only vector-enabled collections support the $vector field. For more information, see Create a collection that can store vector embeddings and $vector in collections (Python).

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Replace a document
result = collection.find_one_and_replace(
    {"_id": "101"},
    {
        "name": "Jane Doe",
        "$vector": [0.08, -0.62, 0.39],
    },
)

print(result)

Insert a new document if no matching document exists

You can use upsert to insert a new document if no document matches the filter criteria.

The new document includes any equality conditions from the filter parameter, as well as any fields you explicitly set in the replacement parameter. If a field is defined both in the filter and in the update, the explicitly set value takes precedence.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Replace a document
collection.find_one_and_replace(
    {
        "$and": [
            {"is_checked_out": False},
            {"number_of_pages": {"$lt": 300}},
        ]
    },
    {"is_checked_out": True, "borrower": "Brook Reed"},
    upsert=True,
)

Include the new document in the response

By default, the response will reflect the document before the replacement. You can specify that you want the response to use the replacement document instead.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment, ReturnDocument

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Replace a document
result = collection.find_one_and_replace(
    {"_id": "101"},
    {"is_checked_out": True, "borrower": "Brook Reed"},
    return_document=ReturnDocument.AFTER,
)

print(result)

Include only specific fields in the response

To specify which fields to include or exclude in the returned document, use a projection.

All fields prefixed with $ are excluded by default and will only be returned if you include them in the projection. _id is included by default and will always be returned unless you exclude it from the projection.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Find a document
result = collection.find_one_and_replace(
    {"metadata.language": "English"},
    {"is_checked_out": True, "borrower": "Brook Reed"},
    projection={"is_checked_out": True, "title": True},
)

print(result)

Exclude specific fields from the response

To specify which fields to include or exclude in the returned document, use a projection.

All fields prefixed with $ are excluded by default and will only be returned if you include them in the projection. _id is included by default and will always be returned unless you exclude it from the projection.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Find a document
result = collection.find_one_and_replace(
    {"metadata.language": "English"},
    {"is_checked_out": True, "borrower": "Brook Reed"},
    projection={"is_checked_out": False, "title": False},
)

print(result)

Work with . and & in field names

You must use & to escape any . or & in field names when the field is used in a filter, sort, projection, update, or indexing clause. Dot notation, which is used to reference nested fields, should not be escaped. For more information, see Work with . and & in field names (Python).

You should not use & to escape any . or & in field names in the replacement document.

The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Find a document
result = collection.find_one_and_replace(
    {
        "$and": [
            {"areas.r&&d": False},
            {"costs.price&.usd": {"$lt": 300}},
        ]
    },
    {
        "areas": {"r&d": False, "design": True},
        "costs": {"price.usd": 100, "price.cad": 90},
    },
)

print(result)

You can also use the escape_field_names function provided by the client:

from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment
from astrapy.utils.document_paths import escape_field_names

# Get an existing collection
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
    "API_ENDPOINT",
    token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
    keyspace="KEYSPACE_NAME",
)
collection = database.get_collection("COLLECTION_NAME")

# Find a document
result = collection.find_one_and_replace(
    {
        "$and": [
            {escape_field_names("areas", "r&d"): False},
            {escape_field_names("costs", "price.usd"): {"$lt": 300}},
        ]
    },
    {
        "areas": {"r&d": False, "design": True},
        "costs": {"price.usd": 100, "price.cad": 90},
    },
)

print(result)

Client reference

For more information, see the client reference.

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