PostgreSQL specific model indexes
The following are PostgreSQL specific indexes available from the django.contrib.postgres.indexes
module.
BloomIndex
class BloomIndex
(\expressions, length=None, columns=(), **options*)
New in Django 3.1.
Creates a bloom index.
To use this index access you need to activate the bloom extension on PostgreSQL. You can install it using the BloomExtension
migration operation.
Provide an integer number of bits from 1 to 4096 to the length
parameter to specify the length of each index entry. PostgreSQL’s default is 80.
The columns
argument takes a tuple or list of up to 32 values that are integer number of bits from 1 to 4095.
Changed in Django Development version:
Positional argument *expressions
was added in order to support functional indexes.
BrinIndex
class BrinIndex
(\expressions, autosummarize=None, pages_per_range=None, **options*)
Creates a BRIN index.
Set the autosummarize
parameter to True
to enable automatic summarization to be performed by autovacuum.
The pages_per_range
argument takes a positive integer.
Changed in Django Development version:
Positional argument *expressions
was added in order to support functional indexes.
BTreeIndex
class BTreeIndex
(\expressions, fillfactor=None, **options*)
Creates a B-Tree index.
Provide an integer value from 10 to 100 to the fillfactor parameter to tune how packed the index pages will be. PostgreSQL’s default is 90.
Changed in Django Development version:
Positional argument *expressions
was added in order to support functional indexes.
GinIndex
class GinIndex
(\expressions, fastupdate=None, gin_pending_list_limit=None, **options*)
Creates a gin index.
To use this index on data types not in the built-in operator classes, you need to activate the btree_gin extension on PostgreSQL. You can install it using the BtreeGinExtension
migration operation.
Set the fastupdate
parameter to False
to disable the GIN Fast Update Technique that’s enabled by default in PostgreSQL.
Provide an integer number of bytes to the gin_pending_list_limit parameter to tune the maximum size of the GIN pending list which is used when fastupdate
is enabled.
Changed in Django Development version:
Positional argument *expressions
was added in order to support functional indexes.
GistIndex
class GistIndex
(\expressions, buffering=None, fillfactor=None, **options*)
Creates a GiST index. These indexes are automatically created on spatial fields with spatial_index=True
. They’re also useful on other types, such as HStoreField
or the range fields.
To use this index on data types not in the built-in gist operator classes, you need to activate the btree_gist extension on PostgreSQL. You can install it using the BtreeGistExtension
migration operation.
Set the buffering
parameter to True
or False
to manually enable or disable buffering build of the index.
Provide an integer value from 10 to 100 to the fillfactor parameter to tune how packed the index pages will be. PostgreSQL’s default is 90.
Changed in Django Development version:
Positional argument *expressions
was added in order to support functional indexes.
HashIndex
class HashIndex
(\expressions, fillfactor=None, **options*)
Creates a hash index.
Provide an integer value from 10 to 100 to the fillfactor parameter to tune how packed the index pages will be. PostgreSQL’s default is 90.
Use this index only on PostgreSQL 10 and later
Hash indexes have been available in PostgreSQL for a long time, but they suffer from a number of data integrity issues in older versions.
Changed in Django Development version:
Positional argument *expressions
was added in order to support functional indexes.
SpGistIndex
class SpGistIndex
(\expressions, fillfactor=None, **options*)
Creates an SP-GiST index.
Provide an integer value from 10 to 100 to the fillfactor parameter to tune how packed the index pages will be. PostgreSQL’s default is 90.
Changed in Django Development version:
Positional argument *expressions
was added in order to support functional indexes.
OpClass()
expressions
New in Django Development version.
class OpClass
(expression, name)
An OpClass()
expression represents the expression
with a custom operator class that can be used to define functional indexes. To use it, you need to add 'django.contrib.postgres'
in your INSTALLED_APPS
. Set the name
parameter to the name of the operator class.
For example:
Index(
OpClass(Lower('username'), name='varchar_pattern_ops'),
name='lower_username_idx',
)
creates an index on Lower('username')
using varchar_pattern_ops
.