Replace a document (Java)

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

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 CollectionUpdateResult, which includes details about the operation.

Parameters

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

Method signature 
CollectionUpdateResult replaceOne(
  Filter filter,
  T replacement
)
CollectionUpdateResult replaceOne(
  Filter filter,
  T replacement,
  CollectionReplaceOneOptions options
)
Name Type Summary

filter

Filter

Optional. 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 (Java).

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

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

T

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.

options

CollectionReplaceOneOptions

Optional. The options for this operation. See Methods of the `CollectionReplaceOneOptions ` class for more details.
Methods of the `CollectionReplaceOneOptions ` class
Method Parameters Summary

sort()

float[] | String | Sort | Map<String, 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 (Java).

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

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()

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

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.

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.commands.results.CollectionUpdateResult;
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;

public class Example {

  public static void main(String[] args) {
    // Get an existing collection
    Collection<Document> collection =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getCollection("COLLECTION_NAME");

    // Replace a document
    Filter filter = Filters.eq("_id", "101");
    Document newDocument = new Document().append("name", "Jane Doe").append("age", 42);
    CollectionUpdateResult result = collection.replaceOne(filter, newDocument);
    System.out.println(result.getMatchedCount());
    System.out.println(result.getModifiedCount());
  }
}

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 (Java).

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.

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.commands.results.CollectionUpdateResult;
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;

public class Example {

  public static void main(String[] args) {
    // Get an existing collection
    Collection<Document> collection =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getCollection("COLLECTION_NAME");

    // Replace a document
    Filter filter =
        Filters.and(Filters.eq("is_checked_out", false), Filters.lt("number_of_pages", 300));
    Document newDocument =
        new Document().append("is_checked_out", true).append("borrower", "Brook Reed");
    CollectionUpdateResult result = collection.replaceOne(filter, newDocument);
    System.out.println(result.getMatchedCount());
    System.out.println(result.getModifiedCount());
  }
}

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 (Java).

The Java client does not support vector search with replaceOne. Instead, you can use findOne to find the _id of a document with vector search, and then use replaceOne and the document’s _id to replace the document. Or, you can use findOneAndReplace.

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 (Java).

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 Java client does not support sorting with replaceOne. Instead, you can use findOne with sorting to find the _id of a document, and then use replaceOne and the document’s _id to replace the document. Or, you can use findOneAndReplace.

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.

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.commands.results.CollectionUpdateResult;
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.Map;
import java.util.Set;

public class Example {

  public static void main(String[] args) {
    // Get an existing collection
    Collection<Document> collection =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getCollection("COLLECTION_NAME");

    // Replace a document
    Filter filter = Filters.eq("metadata.language", "English");
    Document newDocument =
        new Document()
            .append("title", "Hidden Shadows of the Past")
            .append("number_of_pages", 481)
            .append("genres", Set.of("Biography", "Graphic Novel", "Dystopian", "Drama"))
            .append(
                "metadata",
                Map.of(
                    "isbn", "978-1-905585-40-3",
                    "language", "French",
                    "edition", "Anniversary Edition"));
    CollectionUpdateResult result = collection.replaceOne(filter, newDocument);
    System.out.println(result.getMatchedCount());
    System.out.println(result.getModifiedCount());
  }
}

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 (Java).

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.commands.results.CollectionUpdateResult;
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;

public class Example {

  public static void main(String[] args) {
    // Get an existing collection
    Collection<Document> collection =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getCollection("COLLECTION_NAME");

    // Replace a document
    Filter filter = Filters.eq("_id", "101");
    Document newDocument =
        new Document()
            .append("name", "Jane Doe")
            .append("$vector", new float[] {0.08f, -0.62f, 0.39f});
    CollectionUpdateResult result = collection.replaceOne(filter, newDocument);
    System.out.println(result.getMatchedCount());
    System.out.println(result.getModifiedCount());
  }
}

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.

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.commands.options.CollectionReplaceOneOptions;
import com.datastax.astra.client.collections.commands.results.CollectionUpdateResult;
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;

public class Example {

  public static void main(String[] args) {
    // Get an existing collection
    Collection<Document> collection =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getCollection("COLLECTION_NAME");

    // Replace a document
    Filter filter =
        Filters.and(Filters.eq("is_checked_out", false), Filters.lt("number_of_pages", 300));
    Document newDocument =
        new Document().append("is_checked_out", true).append("borrower", "Brook Reed");
    CollectionReplaceOneOptions options = new CollectionReplaceOneOptions().upsert(true);
    CollectionUpdateResult result = collection.replaceOne(filter, newDocument, options);
    System.out.println(result.getMatchedCount());
    System.out.println(result.getModifiedCount());
  }
}

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 (Java).

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

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.commands.results.CollectionUpdateResult;
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.Map;

public class Example {

  public static void main(String[] args) {
    // Get an existing collection
    Collection<Document> collection =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getCollection("COLLECTION_NAME");

    // Find a document
    Filter filter =
        Filters.and(Filters.eq("areas.r&&d", false), Filters.lt("costs.price&.usd", 300));
    Document newDocument =
        new Document()
            .append(
                "areas",
                Map.of(
                    "r&d", false,
                    "design", true))
            .append(
                "costs",
                Map.of(
                    "price.usd", 100,
                    "price.cad", 90));
    CollectionUpdateResult result = collection.replaceOne(filter, newDocument);
    System.out.println(result.getMatchedCount());
    System.out.println(result.getModifiedCount());
  }
}

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

import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.commands.results.CollectionUpdateResult;
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 com.datastax.astra.internal.utils.EscapeUtils;
import java.util.Map;

public class Example {

  public static void main(String[] args) {
    // Get an existing collection
    Collection<Document> collection =
        DataAPIClients.clientHCD("USERNAME", "PASSWORD")
            .getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
            .getCollection("COLLECTION_NAME");

    // Find a document
    Filter filter =
        Filters.and(
            Filters.eq(EscapeUtils.escapeFieldNames("areas", "r&d"), false),
            Filters.lt(EscapeUtils.escapeFieldNames("costs", "price.usd"), 300));
    Document newDocument =
        new Document()
            .append(
                "areas",
                Map.of(
                    "r&d", false,
                    "design", true))
            .append(
                "costs",
                Map.of(
                    "price.usd", 100,
                    "price.cad", 90));
    CollectionUpdateResult result = collection.replaceOne(filter, newDocument);
    System.out.println(result.getMatchedCount());
    System.out.println(result.getModifiedCount());
  }
}

Client reference

For more information, see the client reference.

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