Index classes ease creating database indexes. They can be added using the
Meta.indexes
option. This document
explains the API references of Index
which includes the index
options.
Mengacu pengindeksan siap-pakai
Pengindeksan ditentukan dalam django.db.models.indexes
, tetapi untuk kenyamanan mereka diimpor kedalam django.db.models
. Kebiasaan standar untuk digunakan from django.db import models
dan mengacu ke pengindeksan sebagai models.<IndexClass>
.
Index
¶Index
(fields=(), name=None, db_tablespace=None)[sumber]¶Membuat sebuah index (B-tree) dalam basisdata.
fields
¶Index.
fields
¶Sebuah list atau tuple dari nama dari bidang-bidang dimana indeks diharapkan.
By default, indexes are created with an ascending order for each column. To define an index with a descending order for a column, add a hyphen before the field's name.
For example Index(fields=['headline', '-pub_date'])
would create SQL with
(headline, pub_date DESC)
. Index ordering isn't supported on MySQL. In that
case, a descending index is created as a normal index.
Versi terlama tidak menerima sebuah tuple.
name
¶Index.
name
¶The name of the index. If name
isn't provided Django will auto-generate a
name. For compatibility with different databases, index names cannot be longer
than 30 characters and shouldn't start with a number (0-9) or underscore (_).
db_tablespace
¶Index.
db_tablespace
¶The name of the database tablespace to use for
this index. For single field indexes, if db_tablespace
isn't provided, the
index is created in the db_tablespace
of the field.
If Field.db_tablespace
isn't specified (or if the index uses multiple
fields), the index is created in tablespace specified in the
db_tablespace
option inside the model's
class Meta
. If neither of those tablespaces are set, the index is created
in the same tablespace as the table.
lihat juga
Untuk daftar dari index khusus-PostgreSQL, lihat django.contrib.postgres.indexes
.
Mar 30, 2019