Create a user-defined type (UDT) (Go)

Creates a user-defined type (UDT) to use in a table.

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

Creates a user-defined type with the specified definition.

A successful operation does not return anything.

Parameters

Use the CreateType method, which belongs to the Db type.

Method signature
func (d *Db) CreateType(
  ctx context.Context,
  name string,
  definition table.UDTDefinition,
  opts ...options.CreateTypeOption
) error
Name Type Summary

ctx

context.Context

The context for the operation.

name

string

The name of the new user-defined type.

The name must be unique within the keyspace.

definition

table.UDTDefinition

The definition for the new user-defined type. The definition describes the name and data type of each field in the user-defined type. You can use any supported data type, except for maps, lists, sets, or other user-defined types.

See the examples for usage.

opts

…​options.CreateTypeOption

Optional. The options for this method.

Methods of the CreateTypeOption builder
Method Summary

SetIfNotExists(v bool)

Optional. Whether the command should silently succeed even if a user-defined type with the given name already exists in the keyspace and no new type was created.

This option only checks type names. It does not check type definitions.

Default: false

SetKeyspace(v string)

Optional. The keyspace in which to create the user-defined type.

Default: The working keyspace for the database. This is default_keyspace unless you set a different working keyspace when you created the Db object.

UpdateAPIOptions(v …​APIOption)

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

Examples

The following examples demonstrate how to create a user-defined type.

Create a user-defined type

package main

import (
	"context"
	"log"

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

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

	// Get a database
	client := astra.NewClient()

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

	// Create a user-defined type
	definition := table.UDTDefinition{
		Fields: table.Columns{
			{Name: "name", Column: table.Text()},
			{Name: "is_active", Column: table.Boolean()},
			{Name: "date_joined", Column: table.Date()},
		},
	}
	err := database.CreateType(ctx, "member", definition)
	if err != nil {
		log.Fatal(err)
	}
}

Create a user-defined type only if the type does not exist

Use this option to silently do nothing if a user-defined type with the specified name already exists.

This option only checks type names. It doesn’t check the definition of any existing types.

package main

import (
	"context"
	"log"

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

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

	// Get a database
	client := astra.NewClient()

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

	// Create a user-defined type
	definition := table.UDTDefinition{
		Fields: table.Columns{
			{Name: "name", Column: table.Text()},
			{Name: "is_active", Column: table.Boolean()},
			{Name: "date_joined", Column: table.Date()},
		},
	}
	err := database.CreateType(
		ctx,
		"member",
		definition,
		options.CreateType().SetIfNotExists(true),
	)
	if err != nil {
		log.Fatal(err)
	}
}

Client reference

For more information, see the client reference.

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