Find and replace a document (HTTP)

For details about additional languages, see:

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.

Result

Replaces a document that matches the specified parameters, and returns a dictionary representation of the document. If no document was found, returns null instead of a dictionary representation of the document.

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.

The response also includes details about the operation, such as the number of documents that were modified.

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

Example response:

{
  "data": {
    "document": {
      "_id":"101",
      "name":"John Doe"
    }
  },
  "status":{
    "matchedCount":1,
    "modifiedCount":1
  }
}

Example response if no document was found:

{
  "data":{
    "document":null
  },
  "status":{
    "matchedCount":0,
    "modifiedCount":0
  }
}

Example response if a new document was inserted:

{
  "data":{
    "document":null
  },
  "status":{
    "upsertedId":"7d690267-28f5-47e8-a902-6728f587e84e",
    "matchedCount":0,
    "modifiedCount":0
  }
}

Signature

Use the findOneAndReplace command.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
--header "Token: APPLICATION_TOKEN" \
--header "Content-Type: application/json" \
--data '{
  "findOneAndReplace": {
    "filter": FILTER,
    "replacement": REPLACEMENT,
    "sort": SORT,
    "projection": PROJECTION,
    "options": {
      "upsert": BOOLEAN,
      "returnDocument": RETURN_DOCUMENT_DIRECTIVE
    }
  }
}'

Parameters

Name Type Summary

filter

object

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 (HTTP).

For a list of available filter operators and more examples, see Filter operators for collections (HTTP).

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.

sort

object

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 (HTTP).

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

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 either $vector or $vectorize.

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

replacement

object

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

object

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 (HTTP).

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

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.

options

object

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

upsert

boolean

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

returnDocument

string

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

Can be one of:

  • "before"

  • "after"

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

Default: "before"

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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {
      "_id": "101"
    },
    "replacement": {
      "name": "Jane Doe",
      "age": 42
    }
  }
}'

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 (HTTP).

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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {"$and": [
      {"is_checked_out": false},
      {"number_of_pages": {"$lt": 300}}
    ]},
    "replacement": {
      "is_checked_out": true,
      "borrower": "Brook Reed"
    }
  }
}'

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 (HTTP).

You can provide the search vector as an array of floats, or you can use $binary to provide the search vector as a Base64-encoded string. $binary can be more performant.

For more information about how to convert an array of floats to a Base64-encoded string, see Binary encoding of vector embeddings.

Array of floats
curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "sort": {
      "$vector": [0.08, -0.62, 0.39]
    },
    "replacement": {
      "name": "Jane Doe",
      "age": 42
    }
  }
}'
$binary
curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "sort": {
      "$vector": {"$binary": "PaPXCr8euFI+x64U"}
    },
    "replacement": {
      "name": "Jane Doe",
      "age": 42
    }
  }
}'

Replace a document that is most similar to a search string

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

Vector search with vectorize is only available for collections that have vectorize enabled. For more information, see Create a collection that can automatically generate vector embeddings and $vectorize in collections (HTTP).

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "sort": { "$vectorize": "Text to vectorize" },
    "replacement": {
      "name": "Jane Doe",
      "age": 42
    }
  }
}'

Replace a document based on lexicographical matching

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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {"$lexical": {"$match": "tree hill"}},
    "sort": { "$lexical": "tree hill grassy" },
    "replacement": {
      "is_checked_out": true,
      "borrower": "Brook Reed"
    }
  }
}'

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 (HTTP).

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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": { "metadata.language": "English" },
    "replacement": {
      "is_checked_out": false,
      "number_of_pages": 400
    },
    "sort": {
      "rating": 1,
      "title": -1
    }
  }
}'

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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {"metadata.language": "English"},
    "replacement": {
      "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"
      }
    }
  }
}'

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 (HTTP).

You can provide the vector embeddings as an array of floats, or you can use $binary to provide the vector embeddings as a Base64-encoded string. $binary can be more performant.

For more information about how to convert an array of floats to a Base64-encoded string, see Binary encoding of vector embeddings.

Array of floats
curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {
      "_id": "101"
    },
    "replacement": {
      "name": "Jane Doe",
      "$vector": [0.08, -0.62, 0.39]
    }
  }
}'
$binary
curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {
      "_id": "101"
    },
    "replacement": {
      "name": "Jane Doe",
      "$vector": {"$binary": "PaPXCr8euFI+x64U"}
    }
  }
}'

Use vectorize to generate vector embeddings in the replacement document

Use the reserved $vectorize field to generate a vector embedding automatically. The value of $vectorize can be any string.

Only collections that have vectorize enabled support the $vectorize field. For more information, see Create a collection that can automatically generate vector embeddings and $vectorize in collections (HTTP).

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {
      "_id": "101"
    },
    "replacement": {
      "name": "Jane Doe",
      "$vectorize": "Text to vectorize"
    }
  }
}'

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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {"$and": [
      {"is_checked_out": false},
      {"number_of_pages": {"$lt": 300}}
    ]},
    "replacement": {
      "is_checked_out": true,
      "borrower": "Brook Reed"
    },
    "options": { "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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {
      "_id": "101"
    },
    "replacement": {
      "is_checked_out": true,
      "borrower": "Brook Reed"
    },
    "options": { "returnDocument": "after" }
  }
}'

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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {"metadata.language": "English"},
    "replacement": {
      "is_checked_out": true,
      "borrower": "Brook Reed"
    },
    "projection": {"is_checked_out": true, "title": true}
  }
}'

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.

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {"metadata.language": "English"},
    "replacement": {
      "is_checked_out": true,
      "borrower": "Brook Reed"
    },
    "projection": {"is_checked_out": false, "title": false}
  }
}'

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 (HTTP).

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

curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/COLLECTION_NAME" \
  --header "Token: APPLICATION_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "findOneAndReplace": {
    "filter": {"$and": [
      {"areas.r&&d": false},
      {"costs.price&.usd": {"$lt": 300}}
    ]},
    "replacement": {
      "areas": {
        "r&d": false,
        "design": true
      },
      "costs": {
        "price.usd": 100,
        "price.cad": 90
      }
    }
  }
}'

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