PostgreSQL specific model indexes — Django documentation
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 version 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 version 3.2: 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 toTrue
to enable automatic summarization to be performed by autovacuum.The
pages_per_range
argument takes a positive integer.Changed in version 3.2: 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 version 3.2: 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 toFalse
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 version 3.2: 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 toTrue
orFalse
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 version 3.2: 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 version 3.2: 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 version 3.2: Positional argument
*expressions
was added in order to support functional indexes.
OpClass() expressions
New in version 3.2.
- class OpClass(expression, name)
An
OpClass()
expression represents theexpression
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 :setting:`INSTALLED_APPS`. Set thename
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')
usingvarchar_pattern_ops
.