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.
Referencing built-in indexes
Indexes are defined in django.db.models.indexes, but for convenience
they're imported into django.db.models. The standard convention is
to use from django.db import models and refer to the indexes as
models.<IndexClass>.
Index¶fields¶Index.fields¶A list of the name of the fields on which the index is desired.
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.
Support for column ordering on SQLite
Column ordering is supported on SQLite 3.3.0+ and only for some database file formats. Refer to the SQLite docs for specifics.
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 (_).
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For a list of PostgreSQL-specific indexes, see
django.contrib.postgres.indexes.
Des 02, 2017