Read views: Lua API

This topic describes the Lua API for working with read views.

box.read_view:open({opts})¶

Create a new read view.

Параметры:	opts (table) – (optional) configurations options for a read view. For example, the name option specifies a read view name. If name is not specified, a read view name is set to unknown.
Return:	a created read view object
Rtype:	read_view_object

Example:

tarantool> read_view1 = box.read_view.open({name = 'read_view1'})

object read_view_object¶

An object that represents a read view.

read_view_object:info()¶

Get information about a read view such as a name, status, or ID. All the available fields are listed below in the object options.

Return:	information about a read view
Rtype:	table

read_view_object:close()¶

Close a read view. After the read view is closed, its status is set to closed. On an attempt to use it, an error is raised.

read_view_object.status¶

A read view status. The possible values are open and closed.

Rtype:	string

read_view_object.id¶

A unique numeric identifier of a read view.

Rtype:	number

read_view_object.name¶

A read view name. You can specify a read view name in the box.read_view.open() arguments.

Rtype:	string

read_view_object.is_system¶

Determine whether a read view is system. For example, system read views can be created to make a checkpoint or join a new replica.

Rtype:	boolean

read_view_object.timestamp¶

The fiber.clock() value at the moment of opening a read view.

Rtype:	number

read_view_object.vclock¶

The box.info.vclock value at the moment of opening a read view.

Rtype:	table

read_view_object.signature¶

The box.info.signature value at the moment of opening a read view.

Rtype:	number

read_view_object.space¶

Get access to database spaces included in a read view. You can use this field to query space data.

Rtype:	space object