Add initial support for SQL Server 2005 (Fixes #21)

Author: OskarPersson

sql_server/pyodbc/base.py

@@ -152,6 +152,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
         '08S02',
     )
     _sql_server_versions = {
+        9: 2005,
         10: 2008,
         11: 2012,
         12: 2014,
@@ -210,6 +211,21 @@ def __init__(self, *args, **kwargs):
     def create_cursor(self, name=None):
         return CursorWrapper(self.connection.cursor(), self)
 
+    def _cursor(self):
+        new_conn = False
+
+        if self.connection is None:
+            new_conn = True
+
+        conn = super()._cursor()
+        if new_conn:
+            if self.sql_server_version <= 2005:
+                self.data_types['DateField'] = 'datetime'
+                self.data_types['DateTimeField'] = 'datetime'
+                self.data_types['TimeField'] = 'datetime'
+
+        return conn
+
     def get_connection_params(self):
         settings_dict = self.settings_dict
         if settings_dict['NAME'] == '':
@@ -351,8 +367,7 @@ def init_connection_state(self):
         datefirst = options.get('datefirst', 7)
         cursor.execute('SET DATEFORMAT ymd; SET DATEFIRST %s' % datefirst)
 
-        # http://blogs.msdn.com/b/sqlnativeclient/archive/2008/02/27/microsoft-sql-server-native-client-and-microsoft-sql-server-2008-native-client.aspx
-        val = cursor.execute('SELECT SYSDATETIME()').fetchone()[0]
+        val = self.get_system_datetime()
         if isinstance(val, str):
             raise ImproperlyConfigured(
                 "The database driver doesn't support modern datatime types.")
@@ -365,6 +380,14 @@ def is_usable(self):
         else:
             return True
 
+    def get_system_datetime(self):
+        # http://blogs.msdn.com/b/sqlnativeclient/archive/2008/02/27/microsoft-sql-server-native-client-and-microsoft-sql-server-2008-native-client.aspx
+        with self.temporary_connection() as cursor:
+            if self.sql_server_version <= 2005:
+                return cursor.execute('SELECT GETDATE()').fetchone()[0]
+            else:
+                return cursor.execute('SELECT SYSDATETIME()').fetchone()[0]
+
     @cached_property
     def sql_server_version(self, _known_versions={}):
         """

sql_server/pyodbc/features.py

@@ -1,4 +1,5 @@
 from django.db.backends.base.features import BaseDatabaseFeatures
+from django.utils.functional import cached_property
 
 
 class DatabaseFeatures(BaseDatabaseFeatures):
@@ -21,7 +22,6 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     requires_sqlparse_for_splitting = False
     supports_ignore_conflicts = False
     supports_index_on_text_field = False
-    supports_nullable_unique_constraints = True
     supports_paramstyle_pyformat = False
     supports_partially_nullable_unique_constraints = False
     supports_regex_backreferencing = False
@@ -32,3 +32,19 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     supports_timezones = False
     supports_transactions = True
     uses_savepoints = True
+
+    @cached_property
+    def has_bulk_insert(self):
+        return self.connection.sql_server_version > 2005
+
+    @cached_property
+    def supports_nullable_unique_constraints(self):
+        return self.connection.sql_server_version > 2005
+
+    @cached_property
+    def supports_partial_indexes(self):
+        return self.connection.sql_server_version > 2005
+
+    @cached_property
+    def supports_functions_in_partial_indexes(self):
+        return self.connection.sql_server_version > 2005

sql_server/pyodbc/schema.py

@@ -321,7 +321,9 @@ def _alter_field(self, model, old_field, new_field, old_type, new_type,
             self._delete_primary_key(model, strict)
         # Added a unique?
         if self._unique_should_be_added(old_field, new_field):
-            if not new_field.many_to_many and new_field.null:
+            if (self.connection.features.supports_nullable_unique_constraints and
+                    not new_field.many_to_many and new_field.null):
+
                 self.execute(
                     self._create_index_sql(
                         model, [new_field], sql=self.sql_create_unique_null, suffix="_uniq"
@@ -505,7 +507,9 @@ def add_field(self, model, field):
         if definition is None:
             return
 
-        if not field.many_to_many and field.null and field.unique:
+        if (self.connection.features.supports_nullable_unique_constraints and
+                not field.many_to_many and field.null and field.unique):
+
             definition = definition.replace(' UNIQUE', '')
             self.deferred_sql.append(self._create_index_sql(
                 model, [field], sql=self.sql_create_unique_null, suffix="_uniq"
@@ -554,7 +558,9 @@ def create_model(self, model):
             if definition is None:
                 continue
 
-            if not field.many_to_many and field.null and field.unique:
+            if (self.connection.features.supports_nullable_unique_constraints and
+                    not field.many_to_many and field.null and field.unique):
+
                 definition = definition.replace(' UNIQUE', '')
                 self.deferred_sql.append(self._create_index_sql(
                     model, [field], sql=self.sql_create_unique_null, suffix="_uniq"