Replace a document (Go)

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 an *UpdateResult struct, which indicates the number of documents that were found and the number of documents that were modified.

If specified, the method inserts a new document if no document matches the specified parameters. In this case, the response also includes the _id of the inserted document.

Parameters

Use the ReplaceOne method, which belongs to the Collection type.

Method signature 
func (c *Collection) ReplaceOne(
  ctx context.Context,
  f CollectionFilter,
  replacement any,
  opts ...options.CollectionReplaceOneOption
) (*results.UpdateResult, error)
Name Type Summary

ctx

context.Context

The context for the operation.

f

CollectionFilter

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 (Go).

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

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

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.

opts

…​options.CollectionReplaceOneOption

Optional. A builder to generate options for this operation. See Methods of the CollectionReplaceOneOption builder for more details.
Methods of the CollectionReplaceOneOption builder
Method Summary

SetUpsert(v 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

SetSort(v sort.Sortable)

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 (Go).

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

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.

UpdateAPIOptions(v …​APIOption)

Optional. General API options for this operation, including the timeout.

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.

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.Eq("_id", "101"),

		map[string]any{
			"name": "Jane Doe",
			"age":  42,
		},
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(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 (Go).

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.

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.And(
			filter.Eq("is_checked_out", false),
			filter.Lt("number_of_pages", 300),
		),
		map[string]any{
			"is_checked_out": true,
			"borrower":       "Brook Reed",
		},
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(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 (Go).

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
	"github.com/datastax/astra-db-go/v2/astra/sort"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.F{},
		map[string]any{
			"name": "Jane Doe",
			"age":  42,
		},
		options.CollectionReplaceOne().
			SetSort(sort.Vector([]float32{0.08, -0.62, 0.39})),
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(result)
}

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 (Go).

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
	"github.com/datastax/astra-db-go/v2/astra/sort"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.F{},
		map[string]any{
			"name": "Jane Doe",
			"age":  42,
		},
		options.CollectionReplaceOne().
			SetSort(sort.Vectorize("Text to vectorize")),
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(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 (Go).

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.

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
	"github.com/datastax/astra-db-go/v2/astra/sort"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.Eq("metadata.language", "English"),
		map[string]any{
			"is_checked_out":  false,
			"number_of_pages": 400,
		},
		options.CollectionReplaceOne().
			SetSort(sort.Asc("rating").Desc("title")),
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(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.

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.Eq("metadata.language", "English"),
		map[string]any{
			"title":           "Hidden Shadows of the Past",
			"number_of_pages": 481,
			"genres": []string{
				"Biography",
				"Graphic Novel",
				"Dystopian",
				"Drama",
			},
			"metadata": map[string]any{
				"isbn":     "978-1-905585-40-3",
				"language": "French",
				"edition":  "Anniversary Edition",
			},
		},
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(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 (Go).

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.Eq("_id", "101"),
		map[string]any{
			"name":    "Jane Doe",
			"$vector": []float32{0.08, -0.62, 0.39},
		},
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(result)
}

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 (Go).

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.Eq("_id", "101"),
		map[string]any{
			"name":       "Jane Doe",
			"$vectorize": "Text to vectorize",
		},
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(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.

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.And(
			filter.Eq("is_checked_out", false),
			filter.Lt("number_of_pages", 300),
		),

		map[string]any{
			"is_checked_out": true,
			"borrower":       "Brook Reed",
		},
		options.CollectionReplaceOne().SetUpsert(true),
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(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 (Go).

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

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.And(
			filter.Eq("areas.r&&d", false),
			filter.Lt("costs.price&.usd", 300),
		),
		map[string]any{
			"areas": map[string]any{
				"r&d":    false,
				"design": true,
			},
			"costs": map[string]any{
				"price.usd": 100,
				"price.cad": 90,
			},
		},
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(result)
}

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

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/datastax/astra-db-go/v2/astra"
	"github.com/datastax/astra-db-go/v2/astra/filter"
	"github.com/datastax/astra-db-go/v2/astra/options"
)

func main() {
	ctx := context.Background()

	// Get an existing collection
	client := astra.NewClient()

	database := client.Database(
		"API_ENDPOINT",
		options.API().SetToken("APPLICATION_TOKEN"),
	)

	collection := database.Collection("COLLECTION_NAME")

	// Replace a document
	result, err := collection.ReplaceOne(
		ctx,
		filter.And(
			filter.Eq(astra.EscapeFieldNames("areas", "r&d"), false),
			filter.Lt(astra.EscapeFieldNames("costs", "price.usd"), 300),
		),
		map[string]any{
			"areas": map[string]any{
				"r&d":    false,
				"design": true,
			},
			"costs": map[string]any{
				"price.usd": 100,
				"price.cad": 90,
			},
		},
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(result)
}

Client reference

For more information, see the client reference.

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