Tindakan perpindahan basisdataLink to this heading#

Membuat tambahan menggunakan perpindahanLink to this heading#

Anda dapat membuat tambahan PostgreSQL dalam basisdata anda menggunakan berkas pemindahan. Contoh ini membuat sebuah tambahan hstore, tetapi prinsip-prinsip sama berlaku untuk tambahan-tambahan lain.

Setel tambahan hstore dalam PostgreSQL sebelum tindakan pertama CreateModel atau AddField yang melibatkan HStoreField dengan menambahkan perpindahan dengan tindakan HStoreExtension. Sebagai contoh:

from django.contrib.postgres.operations import HStoreExtension


class Migration(migrations.Migration):
    ...

    operations = [HStoreExtension(), ...]

The operation skips adding the extension if it already exists.

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;.

CreateExtensionLink to this heading#

class CreateExtension(name)Link to this definition#

An Operation subclass which installs a PostgreSQL extension. For common extensions, use one of the more specific subclasses below.

nameLink to this definition#

Ini adalah argumen wajib. Nama dari tambahan untuk dipasang.

BloomExtensionLink to this heading#

class BloomExtensionLink to this definition#

Installs the bloom extension.

BtreeGinExtensionLink to this heading#

class BtreeGinExtensionLink to this definition#

Installs the btree_gin extension.

BtreeGistExtensionLink to this heading#

class BtreeGistExtensionLink to this definition#

Installs the btree_gist extension.

CITextExtensionLink to this heading#

class CITextExtensionLink to this definition#

Pasang tambahan citext.

CryptoExtensionLink to this heading#

class CryptoExtensionLink to this definition#

Pasang tambahan pgcrypto.

HStoreExtensionLink to this heading#

class HStoreExtensionLink to this definition#

Pasang tambahan hstore dan juga setel hubungan pada penterjemah data hstore untuk kemungkinan penggunaan dalam perpindahaan selanjutnya.

TrigramExtensionLink to this heading#

class TrigramExtensionLink to this definition#

Pasang tambahan pg_trm.

UnaccentExtensionLink to this heading#

class UnaccentExtensionLink to this definition#

Pasang tambahan unaccent.

Managing collations using migrationsLink to this heading#

If you need to filter or order a column using a particular collation that your operating system provides but PostgreSQL does not, you can manage collations in your database using a migration file. These collations can then be used with the db_collation parameter on CharField, TextField, and their subclasses.

For example, to create a collation for German phone book ordering:

from django.contrib.postgres.operations import CreateCollation


class Migration(migrations.Migration):
    ...

    operations = [
        CreateCollation(
            "case_insensitive",
            provider="icu",
            locale="und-u-ks-level2",
            deterministic=False,
        ),
        ...,
    ]

class CreateCollation(name, locale, *, provider='libc', deterministic=True)Link to this definition#

Creates a collation with the given name, locale and provider.

Set the deterministic parameter to False to create a non-deterministic collation, such as for case-insensitive filtering.

class RemoveCollation(name, locale, *, provider='libc', deterministic=True)Link to this definition#

Removes the collations named name.

When reversed this is creating a collation with the provided locale, provider, and deterministic arguments. Therefore, locale is required to make this operation reversible.

Concurrent index operationsLink to this heading#

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)Link to this definition#

Like 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)Link to this definition#

Like 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.

Adding constraints without enforcing validationLink to this heading#

PostgreSQL supports the NOT VALID option with the ADD CONSTRAINT statement to add check constraints without enforcing validation on existing rows. This option is useful if you want to skip the potentially lengthy scan of the table to verify that all existing rows satisfy the constraint.

To validate check constraints created with the NOT VALID option at a later point of time, use the ValidateConstraint operation.

Lihat the PostgreSQL documentation untuk rincian lebih.

class AddConstraintNotValid(model_name, constraint)Link to this definition#

Like AddConstraint, but avoids validating the constraint on existing rows.

class ValidateConstraint(model_name, name)Link to this definition#

Scans through the table and validates the given check constraint on existing rows.