============================= Database migration operations ============================= All of these :doc:`operations ` are available from the ``django.contrib.postgres.operations`` module. .. _create-postgresql-extensions: 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 :class:`~django.contrib.postgres.fields.HStoreField` by adding a migration with the :class:`~django.contrib.postgres.operations.HStoreExtension` operation. For example:: from django.contrib.postgres.operations import HStoreExtension class Migration(migrations.Migration): ... operations = [ HStoreExtension(), ... ] For most extensions, this requires a database user with superuser privileges. If the Django database user doesn't have the appropriate privileges, you'll have to create the extension outside of Django migrations with a user that has them. In that case, connect to your Django database and run the query ``CREATE EXTENSION IF NOT EXISTS hstore;``. .. currentmodule:: django.contrib.postgres.operations ``CreateExtension`` =================== .. class:: CreateExtension(name) An ``Operation`` subclass which installs a PostgreSQL extension. For common extensions, use one of the more specific subclasses below. .. attribute:: name This is a required argument. The name of the extension to be installed. ``BloomExtension`` ================== .. class:: BloomExtension() .. versionadded:: 3.1 Installs the ``bloom`` extension. ``BtreeGinExtension`` ===================== .. class:: BtreeGinExtension() Installs the ``btree_gin`` extension. ``BtreeGistExtension`` ====================== .. class:: BtreeGistExtension() Installs 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. Concurrent index operations =========================== .. versionadded:: 3.0 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 :class:`~django.db.migrations.operations.AddIndex`, but creates an index with the ``CONCURRENTLY`` 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 :class:`~django.db.migrations.operations.RemoveIndex`, but removes the index with the ``CONCURRENTLY`` 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 :ref:`non-atomic migration `).