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[wolnelektury.git] / apps / south / db / generic.py
index 09dde03..4a5b512 100644 (file)
@@ -1,10 +1,23 @@
 
 
+import datetime
 from django.core.management.color import no_style
 from django.db import connection, transaction, models
 from django.db.backends.util import truncate_name
 from django.core.management.color import no_style
 from django.db import connection, transaction, models
 from django.db.backends.util import truncate_name
+from django.db.models.fields import NOT_PROVIDED
 from django.dispatch import dispatcher
 from django.conf import settings
 
 from django.dispatch import dispatcher
 from django.conf import settings
 
+
+def alias(attrname):
+    """
+    Returns a function which calls 'attrname' - for function aliasing.
+    We can't just use foo = bar, as this breaks subclassing.
+    """
+    def func(self, *args, **kwds):
+        return getattr(self, attrname)(*args, **kwds)
+    return func
+
+
 class DatabaseOperations(object):
 
     """
 class DatabaseOperations(object):
 
     """
@@ -12,10 +25,14 @@ class DatabaseOperations(object):
     Some of this code comes from Django Evolution.
     """
 
     Some of this code comes from Django Evolution.
     """
 
+    # We assume the generic DB can handle DDL transactions. MySQL wil change this.
+    has_ddl_transactions = True
+
     def __init__(self):
         self.debug = False
         self.deferred_sql = []
     def __init__(self):
         self.debug = False
         self.deferred_sql = []
-
+        self.dry_run = False
+        self.pending_create_signals = []
 
     def execute(self, sql, params=[]):
         """
 
     def execute(self, sql, params=[]):
         """
@@ -25,31 +42,50 @@ class DatabaseOperations(object):
         cursor = connection.cursor()
         if self.debug:
             print "   = %s" % sql, params
         cursor = connection.cursor()
         if self.debug:
             print "   = %s" % sql, params
+
+        if self.dry_run:
+            return []
+
         cursor.execute(sql, params)
         try:
             return cursor.fetchall()
         except:
             return []
         cursor.execute(sql, params)
         try:
             return cursor.fetchall()
         except:
             return []
-            
-            
+
+
     def add_deferred_sql(self, sql):
         """
         Add a SQL statement to the deferred list, that won't be executed until
         this instance's execute_deferred_sql method is run.
         """
         self.deferred_sql.append(sql)
     def add_deferred_sql(self, sql):
         """
         Add a SQL statement to the deferred list, that won't be executed until
         this instance's execute_deferred_sql method is run.
         """
         self.deferred_sql.append(sql)
-        
-        
+
+
     def execute_deferred_sql(self):
         """
         Executes all deferred SQL, resetting the deferred_sql list
         """
         for sql in self.deferred_sql:
             self.execute(sql)
     def execute_deferred_sql(self):
         """
         Executes all deferred SQL, resetting the deferred_sql list
         """
         for sql in self.deferred_sql:
             self.execute(sql)
-            
+
         self.deferred_sql = []
 
 
         self.deferred_sql = []
 
 
+    def clear_deferred_sql(self):
+        """
+        Resets the deferred_sql list to empty.
+        """
+        self.deferred_sql = []
+    
+    
+    def clear_run_data(self):
+        """
+        Resets variables to how they should be before a run. Used for dry runs.
+        """
+        self.clear_deferred_sql()
+        self.pending_create_signals = []
+
+
     def create_table(self, table_name, fields):
         """
         Creates the table 'table_name'. 'fields' is a tuple of fields,
     def create_table(self, table_name, fields):
         """
         Creates the table 'table_name'. 'fields' is a tuple of fields,
@@ -57,14 +93,22 @@ class DatabaseOperations(object):
         django.db.models.fields.Field object
         """
         qn = connection.ops.quote_name
         django.db.models.fields.Field object
         """
         qn = connection.ops.quote_name
+
+        # allow fields to be a dictionary
+        # removed for now - philosophical reasons (this is almost certainly not what you want)
+        #try:
+        #    fields = fields.items()
+        #except AttributeError:
+        #    pass
+
         columns = [
             self.column_sql(table_name, field_name, field)
             for field_name, field in fields
         ]
         columns = [
             self.column_sql(table_name, field_name, field)
             for field_name, field in fields
         ]
-        
+
         self.execute('CREATE TABLE %s (%s);' % (qn(table_name), ', '.join([col for col in columns if col])))
         self.execute('CREATE TABLE %s (%s);' % (qn(table_name), ', '.join([col for col in columns if col])))
-    
-    add_table = create_table # Alias for consistency's sake
+
+    add_table = alias('create_table') # Alias for consistency's sake
 
 
     def rename_table(self, old_table_name, table_name):
 
 
     def rename_table(self, old_table_name, table_name):
@@ -86,16 +130,26 @@ class DatabaseOperations(object):
         qn = connection.ops.quote_name
         params = (qn(table_name), )
         self.execute('DROP TABLE %s;' % params)
         qn = connection.ops.quote_name
         params = (qn(table_name), )
         self.execute('DROP TABLE %s;' % params)
-    
-    drop_table = delete_table
+
+    drop_table = alias('delete_table')
 
 
 
 
-    def add_column(self, table_name, name, field):
+    def clear_table(self, table_name):
+        """
+        Deletes all rows from 'table_name'.
+        """
+        qn = connection.ops.quote_name
+        params = (qn(table_name), )
+        self.execute('DELETE FROM %s;' % params)
+
+    add_column_string = 'ALTER TABLE %s ADD COLUMN %s;'
+
+    def add_column(self, table_name, name, field, keep_default=True):
         """
         Adds the column 'name' to the table 'table_name'.
         Uses the 'field' paramater, a django.db.models.fields.Field instance,
         to generate the necessary sql
         """
         Adds the column 'name' to the table 'table_name'.
         Uses the 'field' paramater, a django.db.models.fields.Field instance,
         to generate the necessary sql
-        
+
         @param table_name: The name of the table to add the column to
         @param name: The name of the column to add
         @param field: The field to use
         @param table_name: The name of the table to add the column to
         @param name: The name of the column to add
         @param field: The field to use
@@ -107,68 +161,82 @@ class DatabaseOperations(object):
                 qn(table_name),
                 sql,
             )
                 qn(table_name),
                 sql,
             )
-            sql = 'ALTER TABLE %s ADD COLUMN %s;' % params
+            sql = self.add_column_string % params
             self.execute(sql)
             self.execute(sql)
-    
-    
+
+            # Now, drop the default if we need to
+            if not keep_default and field.default:
+                field.default = NOT_PROVIDED
+                self.alter_column(table_name, name, field, explicit_name=False)
+
     alter_string_set_type = 'ALTER COLUMN %(column)s TYPE %(type)s'
     alter_string_set_type = 'ALTER COLUMN %(column)s TYPE %(type)s'
-    alter_string_set_null = 'ALTER COLUMN %(column)s SET NOT NULL'
-    alter_string_drop_null = 'ALTER COLUMN %(column)s DROP NOT NULL'
-    
-    def alter_column(self, table_name, name, field):
+    alter_string_set_null = 'ALTER COLUMN %(column)s DROP NOT NULL'
+    alter_string_drop_null = 'ALTER COLUMN %(column)s SET NOT NULL'
+    allows_combined_alters = True
+
+    def alter_column(self, table_name, name, field, explicit_name=True):
         """
         Alters the given column name so it will match the given field.
         Note that conversion between the two by the database must be possible.
         """
         Alters the given column name so it will match the given field.
         Note that conversion between the two by the database must be possible.
-        
+        Will not automatically add _id by default; to have this behavour, pass
+        explicit_name=False.
+
         @param table_name: The name of the table to add the column to
         @param name: The name of the column to alter
         @param field: The new field definition to use
         """
         @param table_name: The name of the table to add the column to
         @param name: The name of the column to alter
         @param field: The new field definition to use
         """
-        
+
         # hook for the field to do any resolution prior to it's attributes being queried
         if hasattr(field, 'south_init'):
             field.south_init()
         # hook for the field to do any resolution prior to it's attributes being queried
         if hasattr(field, 'south_init'):
             field.south_init()
-        
+
         qn = connection.ops.quote_name
         
         qn = connection.ops.quote_name
         
+        # Add _id or whatever if we need to
+        if not explicit_name:
+            field.set_attributes_from_name(name)
+            name = field.column
+
         # First, change the type
         params = {
             "column": qn(name),
             "type": field.db_type(),
         }
         # First, change the type
         params = {
             "column": qn(name),
             "type": field.db_type(),
         }
-        sqls = [self.alter_string_set_type % params]
-        
-        
+
+        # SQLs is a list of (SQL, values) pairs.
+        sqls = [(self.alter_string_set_type % params, [])]
+
         # Next, set any default
         # Next, set any default
-        params = (
-            qn(name),
-        )
-        
         if not field.null and field.has_default():
             default = field.get_default()
         if not field.null and field.has_default():
             default = field.get_default()
-            if isinstance(default, basestring):
-                default = "'%s'" % default
-            params += ("SET DEFAULT %s",)
+            sqls.append(('ALTER COLUMN %s SET DEFAULT %%s ' % (qn(name),), [default]))
         else:
         else:
-            params += ("DROP DEFAULT",)
-        
-        sqls.append('ALTER COLUMN %s %s ' % params)
-        
-        
+            sqls.append(('ALTER COLUMN %s DROP DEFAULT' % (qn(name),), []))
+
+
         # Next, nullity
         params = {
             "column": qn(name),
             "type": field.db_type(),
         }
         if field.null:
         # Next, nullity
         params = {
             "column": qn(name),
             "type": field.db_type(),
         }
         if field.null:
-            sqls.append(self.alter_string_drop_null % params)
+            sqls.append((self.alter_string_set_null % params, []))
         else:
         else:
-            sqls.append(self.alter_string_set_null % params)
-        
-        
+            sqls.append((self.alter_string_drop_null % params, []))
+
+
         # TODO: Unique
         # TODO: Unique
-        
-        self.execute("ALTER TABLE %s %s;" % (qn(table_name), ", ".join(sqls)))
+
+        if self.allows_combined_alters:
+            sqls, values = zip(*sqls)
+            self.execute(
+                "ALTER TABLE %s %s;" % (qn(table_name), ", ".join(sqls)),
+                flatten(values),
+            )
+        else:
+            # Databases like e.g. MySQL don't like more than one alter at once.
+            for sql, values in sqls:
+                self.execute("ALTER TABLE %s %s;" % (qn(table_name), sql), values)
 
 
     def column_sql(self, table_name, field_name, field, tablespace=''):
 
 
     def column_sql(self, table_name, field_name, field, tablespace=''):
@@ -176,13 +244,13 @@ class DatabaseOperations(object):
         Creates the SQL snippet for a column. Used by add_column and add_table.
         """
         qn = connection.ops.quote_name
         Creates the SQL snippet for a column. Used by add_column and add_table.
         """
         qn = connection.ops.quote_name
-        
+
         field.set_attributes_from_name(field_name)
         field.set_attributes_from_name(field_name)
-        
+
         # hook for the field to do any resolution prior to it's attributes being queried
         if hasattr(field, 'south_init'):
             field.south_init()
         # hook for the field to do any resolution prior to it's attributes being queried
         if hasattr(field, 'south_init'):
             field.south_init()
-        
+
         sql = field.db_type()
         if sql:        
             field_output = [qn(field.column), sql]
         sql = field.db_type()
         if sql:        
             field_output = [qn(field.column), sql]
@@ -190,26 +258,40 @@ class DatabaseOperations(object):
             if field.primary_key:
                 field_output.append('PRIMARY KEY')
             elif field.unique:
             if field.primary_key:
                 field_output.append('PRIMARY KEY')
             elif field.unique:
-                field_output.append('UNIQUE')
-        
+                # Instead of using UNIQUE, add a unique index with a predictable name
+                self.add_deferred_sql(
+                    self.create_index_sql(
+                        table_name,
+                        [field.column],
+                        unique = True,
+                        db_tablespace = tablespace,
+                    )
+                )
+
             tablespace = field.db_tablespace or tablespace
             if tablespace and connection.features.supports_tablespaces and field.unique:
                 # We must specify the index tablespace inline, because we
                 # won't be generating a CREATE INDEX statement for this field.
                 field_output.append(connection.ops.tablespace_sql(tablespace, inline=True))
             tablespace = field.db_tablespace or tablespace
             if tablespace and connection.features.supports_tablespaces and field.unique:
                 # We must specify the index tablespace inline, because we
                 # won't be generating a CREATE INDEX statement for this field.
                 field_output.append(connection.ops.tablespace_sql(tablespace, inline=True))
-            
+
             sql = ' '.join(field_output)
             sqlparams = ()
             # if the field is "NOT NULL" and a default value is provided, create the column with it
             # this allows the addition of a NOT NULL field to a table with existing rows
             if not field.null and field.has_default():
                 default = field.get_default()
             sql = ' '.join(field_output)
             sqlparams = ()
             # if the field is "NOT NULL" and a default value is provided, create the column with it
             # this allows the addition of a NOT NULL field to a table with existing rows
             if not field.null and field.has_default():
                 default = field.get_default()
+                # If the default is a callable, then call it!
+                if callable(default):
+                    default = default()
+                # Now do some very cheap quoting. TODO: Redesign return values to avoid this.
                 if isinstance(default, basestring):
                     default = "'%s'" % default.replace("'", "''")
                 if isinstance(default, basestring):
                     default = "'%s'" % default.replace("'", "''")
+                elif isinstance(default, datetime.date):
+                    default = "'%s'" % default
                 sql += " DEFAULT %s"
                 sqlparams = (default)
                 sql += " DEFAULT %s"
                 sqlparams = (default)
-            
-            if field.rel:
+
+            if field.rel and self.supports_foreign_keys:
                 self.add_deferred_sql(
                     self.foreign_key_sql(
                         table_name,
                 self.add_deferred_sql(
                     self.foreign_key_sql(
                         table_name,
@@ -218,10 +300,10 @@ class DatabaseOperations(object):
                         field.rel.to._meta.get_field(field.rel.field_name).column
                     )
                 )
                         field.rel.to._meta.get_field(field.rel.field_name).column
                     )
                 )
-            
+
             if field.db_index and not field.unique:
                 self.add_deferred_sql(self.create_index_sql(table_name, [field.column]))
             if field.db_index and not field.unique:
                 self.add_deferred_sql(self.create_index_sql(table_name, [field.column]))
-            
+
         if hasattr(field, 'post_create_sql'):
             style = no_style()
             for stmt in field.post_create_sql(style, table_name):
         if hasattr(field, 'post_create_sql'):
             style = no_style()
             for stmt in field.post_create_sql(style, table_name):
@@ -231,21 +313,26 @@ class DatabaseOperations(object):
             return sql % sqlparams
         else:
             return None
             return sql % sqlparams
         else:
             return None
-        
+
+
+    supports_foreign_keys = True
+
     def foreign_key_sql(self, from_table_name, from_column_name, to_table_name, to_column_name):
         """
         Generates a full SQL statement to add a foreign key constraint
         """
     def foreign_key_sql(self, from_table_name, from_column_name, to_table_name, to_column_name):
         """
         Generates a full SQL statement to add a foreign key constraint
         """
+        qn = connection.ops.quote_name
         constraint_name = '%s_refs_%s_%x' % (from_column_name, to_column_name, abs(hash((from_table_name, to_table_name))))
         return 'ALTER TABLE %s ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s)%s;' % (
         constraint_name = '%s_refs_%s_%x' % (from_column_name, to_column_name, abs(hash((from_table_name, to_table_name))))
         return 'ALTER TABLE %s ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s)%s;' % (
-            from_table_name,
-            truncate_name(constraint_name, connection.ops.max_name_length()),
-            from_column_name,
-            to_table_name,
-            to_column_name,
+            qn(from_table_name),
+            qn(truncate_name(constraint_name, connection.ops.max_name_length())),
+            qn(from_column_name),
+            qn(to_table_name),
+            qn(to_column_name),
             connection.ops.deferrable_sql() # Django knows this
         )
             connection.ops.deferrable_sql() # Django knows this
         )
-        
+
+
     def create_index_name(self, table_name, column_names):
         """
         Generate a unique name for the index
     def create_index_name(self, table_name, column_names):
         """
         Generate a unique name for the index
@@ -256,45 +343,55 @@ class DatabaseOperations(object):
 
         return '%s_%s%s' % (table_name, column_names[0], index_unique_name)
 
 
         return '%s_%s%s' % (table_name, column_names[0], index_unique_name)
 
+
     def create_index_sql(self, table_name, column_names, unique=False, db_tablespace=''):
         """
         Generates a create index statement on 'table_name' for a list of 'column_names'
         """
     def create_index_sql(self, table_name, column_names, unique=False, db_tablespace=''):
         """
         Generates a create index statement on 'table_name' for a list of 'column_names'
         """
+        qn = connection.ops.quote_name
         if not column_names:
             print "No column names supplied on which to create an index"
             return ''
         if not column_names:
             print "No column names supplied on which to create an index"
             return ''
-            
+
         if db_tablespace and connection.features.supports_tablespaces:
             tablespace_sql = ' ' + connection.ops.tablespace_sql(db_tablespace)
         else:
             tablespace_sql = ''
         if db_tablespace and connection.features.supports_tablespaces:
             tablespace_sql = ' ' + connection.ops.tablespace_sql(db_tablespace)
         else:
             tablespace_sql = ''
-        
+
         index_name = self.create_index_name(table_name, column_names)
         qn = connection.ops.quote_name
         return 'CREATE %sINDEX %s ON %s (%s)%s;' % (
             unique and 'UNIQUE ' or '',
         index_name = self.create_index_name(table_name, column_names)
         qn = connection.ops.quote_name
         return 'CREATE %sINDEX %s ON %s (%s)%s;' % (
             unique and 'UNIQUE ' or '',
-            index_name,
-            table_name,
+            qn(index_name),
+            qn(table_name),
             ','.join([qn(field) for field in column_names]),
             tablespace_sql
             ','.join([qn(field) for field in column_names]),
             tablespace_sql
-            )
-        
+        )
+
     def create_index(self, table_name, column_names, unique=False, db_tablespace=''):
         """ Executes a create index statement """
         sql = self.create_index_sql(table_name, column_names, unique, db_tablespace)
         self.execute(sql)
 
 
     def create_index(self, table_name, column_names, unique=False, db_tablespace=''):
         """ Executes a create index statement """
         sql = self.create_index_sql(table_name, column_names, unique, db_tablespace)
         self.execute(sql)
 
 
+    drop_index_string = 'DROP INDEX %(index_name)s'
+
     def delete_index(self, table_name, column_names, db_tablespace=''):
         """
         Deletes an index created with create_index.
         This is possible using only columns due to the deterministic
         index naming function which relies on column names.
         """
     def delete_index(self, table_name, column_names, db_tablespace=''):
         """
         Deletes an index created with create_index.
         This is possible using only columns due to the deterministic
         index naming function which relies on column names.
         """
+        if isinstance(column_names, (str, unicode)):
+            column_names = [column_names]
         name = self.create_index_name(table_name, column_names)
         name = self.create_index_name(table_name, column_names)
-        sql = "DROP INDEX %s" % name
+        qn = connection.ops.quote_name
+        sql = self.drop_index_string % {"index_name": qn(name), "table_name": qn(table_name)}
         self.execute(sql)
 
         self.execute(sql)
 
+    drop_index = alias('delete_index')
+
+    delete_column_string = 'ALTER TABLE %s DROP COLUMN %s CASCADE;'
 
     def delete_column(self, table_name, name):
         """
 
     def delete_column(self, table_name, name):
         """
@@ -302,7 +399,9 @@ class DatabaseOperations(object):
         """
         qn = connection.ops.quote_name
         params = (qn(table_name), qn(name))
         """
         qn = connection.ops.quote_name
         params = (qn(table_name), qn(name))
-        self.execute('ALTER TABLE %s DROP COLUMN %s CASCADE;' % params, [])
+        self.execute(self.delete_column_string % params, [])
+
+    drop_column = alias('delete_column')
 
 
     def rename_column(self, table_name, old, new):
 
 
     def rename_column(self, table_name, old, new):
@@ -317,6 +416,8 @@ class DatabaseOperations(object):
         Makes sure the following commands are inside a transaction.
         Must be followed by a (commit|rollback)_transaction call.
         """
         Makes sure the following commands are inside a transaction.
         Must be followed by a (commit|rollback)_transaction call.
         """
+        if self.dry_run:
+            return
         transaction.commit_unless_managed()
         transaction.enter_transaction_management()
         transaction.managed(True)
         transaction.commit_unless_managed()
         transaction.enter_transaction_management()
         transaction.managed(True)
@@ -327,6 +428,8 @@ class DatabaseOperations(object):
         Commits the current transaction.
         Must be preceded by a start_transaction call.
         """
         Commits the current transaction.
         Must be preceded by a start_transaction call.
         """
+        if self.dry_run:
+            return
         transaction.commit()
         transaction.leave_transaction_management()
 
         transaction.commit()
         transaction.leave_transaction_management()
 
@@ -336,53 +439,67 @@ class DatabaseOperations(object):
         Rolls back the current transaction.
         Must be preceded by a start_transaction call.
         """
         Rolls back the current transaction.
         Must be preceded by a start_transaction call.
         """
+        if self.dry_run:
+            return
         transaction.rollback()
         transaction.leave_transaction_management()
         transaction.rollback()
         transaction.leave_transaction_management()
-    
-    
+
+
     def send_create_signal(self, app_label, model_names):
     def send_create_signal(self, app_label, model_names):
+        self.pending_create_signals.append((app_label, model_names))
+
+
+    def send_pending_create_signals(self):
+        for (app_label, model_names) in self.pending_create_signals:
+            self.really_send_create_signal(app_label, model_names)
+        self.pending_create_signals = []
+
+
+    def really_send_create_signal(self, app_label, model_names):
         """
         Sends a post_syncdb signal for the model specified.
         """
         Sends a post_syncdb signal for the model specified.
-        
+
         If the model is not found (perhaps it's been deleted?),
         no signal is sent.
         If the model is not found (perhaps it's been deleted?),
         no signal is sent.
-        
+
         TODO: The behavior of django.contrib.* apps seems flawed in that
         they don't respect created_models.  Rather, they blindly execute
         over all models within the app sending the signal.  This is a
         patch we should push Django to make  For now, this should work.
         """
         TODO: The behavior of django.contrib.* apps seems flawed in that
         they don't respect created_models.  Rather, they blindly execute
         over all models within the app sending the signal.  This is a
         patch we should push Django to make  For now, this should work.
         """
+        if self.debug:
+            print " - Sending post_syncdb signal for %s: %s" % (app_label, model_names)
         app = models.get_app(app_label)
         if not app:
             return
         app = models.get_app(app_label)
         if not app:
             return
-            
+
         created_models = []
         for model_name in model_names:
             model = models.get_model(app_label, model_name)
             if model:
                 created_models.append(model)
         created_models = []
         for model_name in model_names:
             model = models.get_model(app_label, model_name)
             if model:
                 created_models.append(model)
-                
+
         if created_models:
             # syncdb defaults -- perhaps take these as options?
             verbosity = 1
             interactive = True
         if created_models:
             # syncdb defaults -- perhaps take these as options?
             verbosity = 1
             interactive = True
-            
+
             if hasattr(dispatcher, "send"):
                 dispatcher.send(signal=models.signals.post_syncdb, sender=app,
             if hasattr(dispatcher, "send"):
                 dispatcher.send(signal=models.signals.post_syncdb, sender=app,
-                app=app, created_models=created_models,
-                verbosity=verbosity, interactive=interactive)
+                                app=app, created_models=created_models,
+                                verbosity=verbosity, interactive=interactive)
             else:
                 models.signals.post_syncdb.send(sender=app,
             else:
                 models.signals.post_syncdb.send(sender=app,
-                app=app, created_models=created_models,
-                verbosity=verbosity, interactive=interactive)
-                
+                                                app=app, created_models=created_models,
+                                                verbosity=verbosity, interactive=interactive)
+
     def mock_model(self, model_name, db_table, db_tablespace='', 
     def mock_model(self, model_name, db_table, db_tablespace='', 
-                    pk_field_name='id', pk_field_type=models.AutoField,
-                    pk_field_kwargs={}):
+                   pk_field_name='id', pk_field_type=models.AutoField,
+                   pk_field_args=[], pk_field_kwargs={}):
         """
         Generates a MockModel class that provides enough information
         to be used by a foreign key/many-to-many relationship.
         """
         Generates a MockModel class that provides enough information
         to be used by a foreign key/many-to-many relationship.
-        
+
         Migrations should prefer to use these rather than actual models
         as models could get deleted over time, but these can remain in
         migration files forever.
         Migrations should prefer to use these rather than actual models
         as models could get deleted over time, but these can remain in
         migration files forever.
@@ -397,7 +514,7 @@ class DatabaseOperations(object):
                 if pk_field_type == models.AutoField:
                     pk_field_kwargs['primary_key'] = True
 
                 if pk_field_type == models.AutoField:
                     pk_field_kwargs['primary_key'] = True
 
-                self.pk = pk_field_type(**pk_field_kwargs)
+                self.pk = pk_field_type(*pk_field_args, **pk_field_kwargs)
                 self.pk.set_attributes_from_name(pk_field_name)
                 self.abstract = False
 
                 self.pk.set_attributes_from_name(pk_field_name)
                 self.abstract = False
 
@@ -416,3 +533,11 @@ class DatabaseOperations(object):
         MockModel._meta = MockOptions()
         MockModel._meta.model = MockModel
         return MockModel
         MockModel._meta = MockOptions()
         MockModel._meta.model = MockModel
         return MockModel
+
+# Single-level flattening of lists
+def flatten(ls):
+    nl = []
+    for l in ls:
+        nl += l
+    return nl
+