Database migration operations
All of these operations are available from the django.contrib.postgres.operations
module.
Creating extension using migrations
You can create a PostgreSQL extension in your database using a migration file. This example creates an hstore extension, but the same principles apply for other extensions.
Set up the hstore extension in PostgreSQL before the first CreateModel
or AddField
operation that involves HStoreField
by adding a migration with the HStoreExtension
operation. For example:
from django.contrib.postgres.operations import HStoreExtension class Migration(migrations.Migration): ... operations = [ HStoreExtension(), ... ]
Creating the extension requires a database user with superuser privileges. If the Django database user doesn’t have superuser privileges, you’ll have to create the extension outside of Django migrations with a user that has the appropriate privileges. In that case, connect to your Django database and run the query CREATE EXTENSION IF NOT EXISTS hstore;
.
CreateExtension
-
class CreateExtension(name)
-
An
Operation
subclass which installs PostgreSQL extensions.-
name
-
This is a required argument. The name of the extension to be installed.
-
BtreeGinExtension
-
class BtreeGinExtension
-
Install the
btree_gin
extension.
BtreeGistExtension
-
class BtreeGistExtension
-
Install the
btree_gist
extension.
CITextExtension
-
class CITextExtension
-
Installs the
citext
extension.
CryptoExtension
-
class CryptoExtension
-
Installs the
pgcrypto
extension.
HStoreExtension
-
class HStoreExtension
-
Installs the
hstore
extension and also sets up the connection to interpret hstore data for possible use in subsequent migrations.
TrigramExtension
-
class TrigramExtension
-
Installs the
pg_trgm
extension.
UnaccentExtension
-
class UnaccentExtension
-
Installs the
unaccent
extension.
Index concurrent operations
PostgreSQL supports the CONCURRENTLY
option to CREATE INDEX
and DROP INDEX
statements to add and remove indexes without locking out writes. This option is useful for adding or removing an index in a live production database.
-
class AddIndexConcurrently(model_name, index)
-
Like
AddIndex
, but creates an index with theCONCURRENTLY
option. This has a few caveats to be aware of when using this option, see the PostgreSQL documentation of building indexes concurrently.
-
class RemoveIndexConcurrently(model_name, name)
-
Like
RemoveIndex
, but removes the index with theCONCURRENTLY
option. This has a few caveats to be aware of when using this option, see the PostgreSQL documentation.
Note
The CONCURRENTLY
option is not supported inside a transaction (see non-atomic migration).
© Django Software Foundation and individual contributors
Licensed under the BSD License.
https://docs.djangoproject.com/en/3.0/ref/contrib/postgres/operations/