From c4b2a3262cc79383d6562cfc7e9af20135c8e0bf Mon Sep 17 00:00:00 2001 From: Andrew Godwin Date: Fri, 10 Aug 2012 12:38:18 +0100 Subject: [PATCH] Add support for unique_together --- django/db/backends/schema.py | 53 ++++++++++++++++++++++++++++++- tests/modeltests/schema/models.py | 12 +++++++ tests/modeltests/schema/tests.py | 48 ++++++++++++++++++++++++++-- 3 files changed, 110 insertions(+), 3 deletions(-) diff --git a/django/db/backends/schema.py b/django/db/backends/schema.py index 5f4e0146b4..c5e297197b 100644 --- a/django/db/backends/schema.py +++ b/django/db/backends/schema.py @@ -29,6 +29,7 @@ class BaseDatabaseSchemaEditor(object): # Overrideable SQL templates sql_create_table = "CREATE TABLE %(table)s (%(definition)s)" + sql_create_table_unique = "UNIQUE (%(columns)s)" sql_rename_table = "ALTER TABLE %(old_table)s RENAME TO %(new_table)s" sql_delete_table = "DROP TABLE %(table)s CASCADE" @@ -51,7 +52,7 @@ class BaseDatabaseSchemaEditor(object): sql_create_fk = "ALTER TABLE %(table)s ADD CONSTRAINT %(name)s FOREIGN KEY (%(column)s) REFERENCES %(to_table)s (%(to_column)s) DEFERRABLE INITIALLY DEFERRED" sql_delete_fk = "ALTER TABLE %(table)s DROP CONSTRAINT %(name)s" - sql_create_index = "CREATE %(unique)s INDEX %(name)s ON %(table)s (%(columns)s)%s;" + sql_create_index = "CREATE %(unique)s INDEX %(name)s ON %(table)s (%(columns)s)%(extra)s;" sql_delete_index = "DROP INDEX %(name)s" sql_create_pk = "ALTER TABLE %(table)s ADD CONSTRAINT %(constraint)s PRIMARY KEY (%(columns)s)" @@ -174,6 +175,17 @@ class BaseDatabaseSchemaEditor(object): definition, )) params.extend(extra_params) + # Indexes + if field.db_index: + self.deferred_sql.append( + self.sql_create_index % { + "unique": "", + "name": self._create_index_name(model, [field.column], suffix=""), + "table": self.quote_name(model._meta.db_table), + "columns": self.quote_name(field.column), + "extra": "", + } + ) # FK if field.rel: to_table = field.rel.to._meta.db_table @@ -191,6 +203,12 @@ class BaseDatabaseSchemaEditor(object): "to_column": self.quote_name(to_column), } ) + # Add any unique_togethers + for fields in model._meta.unique_together: + columns = [model._meta.get_field_by_name(field)[0].column for field in fields] + column_sqls.append(self.sql_create_table_unique % { + "columns": ", ".join(self.quote_name(column) for column in columns), + }) # Make the table sql = self.sql_create_table % { "table": model._meta.db_table, @@ -210,6 +228,39 @@ class BaseDatabaseSchemaEditor(object): "table": self.quote_name(model._meta.db_table), }) + def alter_unique_together(self, model, old_unique_together, new_unique_together): + """ + Deals with a model changing its unique_together. + Note: The input unique_togethers must be doubly-nested, not the single- + nested ["foo", "bar"] format. + """ + olds = set(frozenset(fields) for fields in old_unique_together) + news = set(frozenset(fields) for fields in new_unique_together) + # Deleted uniques + for fields in olds.difference(news): + columns = [model._meta.get_field_by_name(field)[0].column for field in fields] + constraint_names = self._constraint_names(model, list(columns), unique=True) + if len(constraint_names) != 1: + raise ValueError("Found wrong number (%s) of constraints for %s(%s)" % ( + len(constraint_names), + model._meta.db_table, + ", ".join(columns), + )) + self.execute( + self.sql_delete_unique % { + "table": self.quote_name(model._meta.db_table), + "name": constraint_names[0], + }, + ) + # Created uniques + for fields in news.difference(olds): + columns = [model._meta.get_field_by_name(field)[0].column for field in fields] + self.execute(self.sql_create_unique % { + "table": self.quote_name(model._meta.db_table), + "name": self._create_index_name(model, columns, suffix="_uniq"), + "columns": ", ".join(self.quote_name(column) for column in columns), + }) + def create_field(self, model, field, keep_default=False): """ Creates a field on a model. diff --git a/tests/modeltests/schema/models.py b/tests/modeltests/schema/models.py index 2362718bf3..e9eba1fc6f 100644 --- a/tests/modeltests/schema/models.py +++ b/tests/modeltests/schema/models.py @@ -32,3 +32,15 @@ class Book(models.Model): class Tag(models.Model): title = models.CharField(max_length=255) slug = models.SlugField(unique=True) + + class Meta: + managed = False + + +class UniqueTest(models.Model): + year = models.IntegerField() + slug = models.SlugField(unique=False) + + class Meta: + managed = False + unique_together = ["year", "slug"] diff --git a/tests/modeltests/schema/tests.py b/tests/modeltests/schema/tests.py index 8708fd7c8d..52d99225f0 100644 --- a/tests/modeltests/schema/tests.py +++ b/tests/modeltests/schema/tests.py @@ -6,7 +6,7 @@ from django.db import connection, DatabaseError, IntegrityError from django.db.models.fields import IntegerField, TextField, CharField, SlugField from django.db.models.fields.related import ManyToManyField from django.db.models.loading import cache -from .models import Author, Book, AuthorWithM2M, Tag +from .models import Author, Book, AuthorWithM2M, Tag, UniqueTest class SchemaTests(TestCase): @@ -18,7 +18,7 @@ class SchemaTests(TestCase): as the code it is testing. """ - models = [Author, Book, AuthorWithM2M, Tag] + models = [Author, Book, AuthorWithM2M, Tag, UniqueTest] # Utility functions @@ -298,3 +298,47 @@ class SchemaTests(TestCase): Tag.objects.create(title="foo", slug="foo") self.assertRaises(IntegrityError, Tag.objects.create, title="bar", slug="foo") connection.rollback() + + def test_unique_together(self): + """ + Tests removing and adding unique_together constraints on a model. + """ + # Create the table + editor = connection.schema_editor() + editor.start() + editor.create_model(UniqueTest) + editor.commit() + # Ensure the fields are unique to begin with + UniqueTest.objects.create(year=2012, slug="foo") + UniqueTest.objects.create(year=2011, slug="foo") + UniqueTest.objects.create(year=2011, slug="bar") + self.assertRaises(IntegrityError, UniqueTest.objects.create, year=2012, slug="foo") + connection.rollback() + # Alter the model to it's non-unique-together companion + editor = connection.schema_editor() + editor.start() + editor.alter_unique_together( + UniqueTest, + UniqueTest._meta.unique_together, + [], + ) + editor.commit() + # Ensure the fields are no longer unique + UniqueTest.objects.create(year=2012, slug="foo") + UniqueTest.objects.create(year=2012, slug="foo") + connection.rollback() + # Alter it back + new_new_field = SlugField(unique=True) + new_new_field.set_attributes_from_name("slug") + editor = connection.schema_editor() + editor.start() + editor.alter_unique_together( + UniqueTest, + [], + UniqueTest._meta.unique_together, + ) + editor.commit() + # Ensure the fields are unique again + UniqueTest.objects.create(year=2012, slug="foo") + self.assertRaises(IntegrityError, UniqueTest.objects.create, year=2012, slug="foo") + connection.rollback()