Commit f8c3d38c authored by Tim Graham's avatar Tim Graham
Browse files

[1.8.x] Fixed #26034 -- Fixed incorrect index handling on PostgreSQL on... 

[1.8.x] Fixed #26034 -- Fixed incorrect index handling on PostgreSQL on Char/TextField with unique=True and db_index=True.

Thanks Simon Charette for review.

Backport of 56aaae58 from master
parent fe5d37f9

django/db/backends/postgresql_psycopg2/schema.py

+2 −2
Original line number Diff line number Diff line
@@ -107,13 +107,13 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor): 
            new_db_params, strict,

        )

        # Added an index? Create any PostgreSQL-specific indexes.

        if ((not old_field.db_index and new_field.db_index) or (not old_field.unique and new_field.unique)):

        if not old_field.db_index and not old_field.unique and (new_field.db_index or new_field.unique):

            like_index_statement = self._create_like_index_sql(model, new_field)

            if like_index_statement is not None:

                self.execute(like_index_statement)



        # Removed an index? Drop any PostgreSQL-specific indexes.

        if ((not new_field.db_index and old_field.db_index) or (not new_field.unique and old_field.unique)):

        if (old_field.db_index or old_field.unique) and not (new_field.db_index or new_field.unique):

            index_to_remove = self._create_index_name(model, [old_field.column], suffix='_like')

            index_names = self._constraint_names(model, [old_field.column], index=True)

            for index_name in index_names:

docs/releases/1.8.9.txt

+5 −0
Original line number Diff line number Diff line
@@ -18,3 +18,8 @@ Bugfixes 
* Fixed a regression that caused the incorrect day to be selected when opening

  the admin calendar widget for timezones from GMT+0100 to GMT+1200

  (:ticket:`24980`).



* Fixed incorrect index handling in migrations on PostgreSQL when adding

  ``db_index=True`` or ``unique=True`` to a ``CharField`` or ``TextField`` that

  already had the other specified, or when removing one of them from a field

  that had both (:ticket:`26034`).

tests/schema/tests.py

+42 −0
Original line number Diff line number Diff line
@@ -1592,3 +1592,45 @@ class SchemaTests(TransactionTestCase): 
        with connection.schema_editor() as editor:

            editor.alter_field(Note, new_field, old_field, strict=True)

        self.assertEqual(self.get_constraints_for_column(Note, 'info'), [])



    @unittest.skipUnless(connection.vendor == 'postgresql', "PostgreSQL specific")

    def test_alter_field_add_unique_to_charfield_with_db_index(self):

        # Create the table and verify initial indexes.

        with connection.schema_editor() as editor:

            editor.create_model(BookWithoutAuthor)

        self.assertEqual(len(self.get_constraints_for_column(BookWithoutAuthor, 'title')), 2)

        # Alter to add unique=True (should add 1 index)

        old_field = BookWithoutAuthor._meta.get_field('title')

        new_field = CharField(max_length=100, db_index=True, unique=True)

        new_field.set_attributes_from_name('title')

        with connection.schema_editor() as editor:

            editor.alter_field(BookWithoutAuthor, old_field, new_field, strict=True)

        self.assertEqual(len(self.get_constraints_for_column(BookWithoutAuthor, 'title')), 3)

        # Alter to remove unique=True (should drop unique index) # XXX: bug!

        old_field = BookWithoutAuthor._meta.get_field('title')

        new_field = CharField(max_length=100, db_index=True)

        new_field.set_attributes_from_name('title')

        with connection.schema_editor() as editor:

            editor.alter_field(BookWithoutAuthor, old_field, new_field, strict=True)

        self.assertEqual(len(self.get_constraints_for_column(BookWithoutAuthor, 'title')), 3)



    @unittest.skipUnless(connection.vendor == 'postgresql', "PostgreSQL specific")

    def test_alter_field_add_db_index_to_charfield_with_unique(self):

        # Create the table and verify initial indexes.

        with connection.schema_editor() as editor:

            editor.create_model(Tag)

        self.assertEqual(len(self.get_constraints_for_column(Tag, 'slug')), 2)

        # Alter to add db_index=True

        old_field = Tag._meta.get_field('slug')

        new_field = SlugField(db_index=True, unique=True)

        new_field.set_attributes_from_name('slug')

        with connection.schema_editor() as editor:

            editor.alter_field(Tag, old_field, new_field, strict=True)

        self.assertEqual(len(self.get_constraints_for_column(Tag, 'slug')), 2)

        # Alter to remove db_index=True

        old_field = Tag._meta.get_field('slug')

        new_field = SlugField(unique=True)

        new_field.set_attributes_from_name('slug')

        with connection.schema_editor() as editor:

            editor.alter_field(Tag, old_field, new_field, strict=True)

        self.assertEqual(len(self.get_constraints_for_column(Tag, 'slug')), 2)