box.schema.space.create()

space_opts

object space_opts¶

Space options that include the space id, format, field count, constraints and foreign keys, and so on. These options are passed to the box.schema.space.create() method.

Примечание

These options are also passed to space_object:alter().

space_opts.if_not_exists¶

Create a space only if a space with the same name does not exist already. Otherwise, do nothing but do not cause an error.

Type: boolean

Default: false

space_opts.engine¶

A storage engine.

Type: string

Default: memtx

Possible values: memtx, vinyl

space_opts.id¶

A unique numeric identifier of the space: users can refer to spaces with this id instead of the name.

Type: number

Default: last space’s ID + 1

space_opts.field_count¶

A fixed count of fields. For example, if field_count=5, it is illegal to insert a tuple with fewer than or more than 5 fields.

Type: number

Default: 0 (not fixed)

space_opts.user¶

The name of the user who is considered to be the space’s owner for authorization purposes.

Type: string

Default: current user’s name

space_opts.format¶

Field names and types. See the illustrations of format clauses in the space_object:format() description and in the box.space._space example. Optional and usually not specified.

Type: table

Default: blank

space_opts.is_local¶

Space contents are replication-local: changes are stored in the write-ahead log of the local node but there is no replication.

Type: boolean

Default: false

space_opts.temporary¶

Space contents are temporary: changes are not stored in the write-ahead log and there is no replication.

Примечание

Vinyl does not support temporary spaces.

Type: boolean

Default: false

space_opts.is_sync¶

Any transaction doing a DML request on this space becomes synchronous.

Пример:

box.schema.space.create('bands', { is_sync = true })

Type: boolean

Default: false

space_opts.constraint¶

The constraints that space tuples must satisfy.

Type: table

Default: blank

Пример:

-- Define a tuple constraint function --
box.schema.func.create('check_person', {
    language = 'LUA',
    is_deterministic = true,
    body = 'function(t, c) return (t.age >= 0 and #(t.name) > 3) end'
})

-- Create a space with a tuple constraint --
customers = box.schema.space.create('customers', {constraint = 'check_person'})

space_opts.foreign_key¶

The foreign keys for space fields.

Type: table

Default: blank

Пример:

-- Create a space with a tuple foreign key --
box.schema.space.create("orders", {
    foreign_key = {
        space = 'customers',
        field = {customer_id = 'id', customer_name = 'name'}
    }
})

box.space.orders:format({
    {name = "id", type = "number"},
    {name = "customer_id" },
    {name = "customer_name"},
    {name = "price_total", type = "number"},
})

Если выполнить box.cfg{read_only=true...} во время конфигурации по-разному влияет на спейсы в зависимости от опций, использованных во время box.schema.space.create, как описано в таблице:

Характеристика	Можно создать?	Допускает запись?	Реплицируется?	Сохраняется?
(по умолчанию)	нет	нет	да	да
temporary (временный)	нет	да	нет	нет
is_local	нет	да	нет	да

Пример:

tarantool> s = box.schema.space.create('space55')
---
...
tarantool> s = box.schema.space.create('space55', {
         >   id = 555,
         >   temporary = false
         > })
---
- error: Space 'space55' already exists
...
tarantool> s = box.schema.space.create('space55', {
         >   if_not_exists = true
         > })
---
...