From b105a528828377757e3c654bcd3221406409ab25 Mon Sep 17 00:00:00 2001
From: Adrian Holovaty <adrian@holovaty.com>
Date: Mon, 20 Aug 2007 03:08:32 +0000
Subject: [PATCH] Refactored get_drop_sequence() to
 DatabaseOperations.drop_sequence_sql(). Refs #5106

git-svn-id: http://code.djangoproject.com/svn/django/trunk@5978 bcc190cf-cafb-0310-a4f2-bffc1f526a37
---
 django/core/management/sql.py     | 11 +++++++----
 django/db/backends/__init__.py    |  7 +++++++
 django/db/backends/oracle/base.py |  6 +++---
 3 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/django/core/management/sql.py b/django/core/management/sql.py
index 4db32fda74..2c495e40dd 100644
--- a/django/core/management/sql.py
+++ b/django/core/management/sql.py
@@ -151,8 +151,10 @@ def sql_delete(app, style):
                         style.SQL_KEYWORD(connection.ops.drop_foreignkey_sql()),
                         style.SQL_FIELD(truncate_name(r_name, connection.ops.max_name_length()))))
                 del references_to_delete[model]
-            if model._meta.has_auto_field and hasattr(backend, 'get_drop_sequence'):
-                output.append(backend.get_drop_sequence(model._meta.db_table))
+            if model._meta.has_auto_field:
+                ds = connection.ops.drop_sequence_sql(model._meta.db_table)
+                if ds:
+                    output.append(ds)
 
     # Output DROP TABLE statements for many-to-many tables.
     for model in app_models:
@@ -161,8 +163,9 @@ def sql_delete(app, style):
             if cursor and table_name_converter(f.m2m_db_table()) in table_names:
                 output.append("%s %s;" % (style.SQL_KEYWORD('DROP TABLE'),
                     style.SQL_TABLE(qn(f.m2m_db_table()))))
-                if hasattr(backend, 'get_drop_sequence'):
-                    output.append(backend.get_drop_sequence("%s_%s" % (model._meta.db_table, f.column)))
+                ds = connection.ops.drop_sequence_sql("%s_%s" % (model._meta.db_table, f.column))
+                if ds:
+                    output.append(ds)
 
     app_label = app_models[0]._meta.app_label
 
diff --git a/django/db/backends/__init__.py b/django/db/backends/__init__.py
index 01cc025608..f3c6f59258 100644
--- a/django/db/backends/__init__.py
+++ b/django/db/backends/__init__.py
@@ -103,6 +103,13 @@ class BaseDatabaseOperations(object):
         """
         return "DROP CONSTRAINT"
 
+    def drop_sequence_sql(self, table):
+        """
+        Returns any SQL necessary to drop the sequence for the given table.
+        Returns None if no SQL is necessary.
+        """
+        return None
+
     def field_cast_sql(self, db_type):
         """
         Given a column type (e.g. 'BLOB', 'VARCHAR'), returns the SQL necessary
diff --git a/django/db/backends/oracle/base.py b/django/db/backends/oracle/base.py
index 1a23d36709..578576a26f 100644
--- a/django/db/backends/oracle/base.py
+++ b/django/db/backends/oracle/base.py
@@ -66,6 +66,9 @@ class DatabaseOperations(BaseDatabaseOperations):
     def deferrable_sql(self):
         return " DEFERRABLE INITIALLY DEFERRED"
 
+    def drop_sequence_sql(self, table):
+        return "DROP SEQUENCE %s;" % self.quote_name(get_sequence_name(table))
+
     def field_cast_sql(self, db_type):
         if db_type.endswith('LOB'):
             return "DBMS_LOB.SUBSTR(%s)"
@@ -468,9 +471,6 @@ def to_unicode(s):
         return force_unicode(s)
     return s
 
-def get_drop_sequence(table):
-    return "DROP SEQUENCE %s;" % DatabaseOperations().quote_name(get_sequence_name(table))
-
 def _get_sequence_reset_sql():
     # TODO: colorize this SQL code with style.SQL_KEYWORD(), etc.
     return """