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, thename
option specifies a read view name. Ifname
is not specified, a read view name is set tounknown
.
Return: a created read view object
Rtype: Example:
tarantool> read_view1 = box.read_view.open({name = 'read_view1'})
- opts (
-
object
read_view_object
¶ An object that represents a read view.
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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
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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
andclosed
.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
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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
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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
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