diff --git a/django/db/backends/oracle/features.py b/django/db/backends/oracle/features.py index ffa5c6474c..0b152e612e 100644 --- a/django/db/backends/oracle/features.py +++ b/django/db/backends/oracle/features.py @@ -35,7 +35,6 @@ class DatabaseFeatures(BaseDatabaseFeatures): supports_combined_alters = False nulls_order_largest = True requires_literal_defaults = True - connection_persists_old_columns = True closed_cursor_error_class = InterfaceError bare_select_suffix = " FROM DUAL" uppercases_column_names = True diff --git a/django/db/backends/oracle/introspection.py b/django/db/backends/oracle/introspection.py index 3596368b6b..c058418ec3 100644 --- a/django/db/backends/oracle/introspection.py +++ b/django/db/backends/oracle/introspection.py @@ -33,6 +33,8 @@ class DatabaseIntrospection(BaseDatabaseIntrospection): except AttributeError: pass + cache_bust_counter = 1 + def get_field_type(self, data_type, description): # If it's a NUMBER with scale == 0, consider it an IntegerField if data_type == cx_Oracle.NUMBER: @@ -59,7 +61,10 @@ class DatabaseIntrospection(BaseDatabaseIntrospection): def get_table_description(self, cursor, table_name): "Returns a description of the table, with the DB-API cursor.description interface." - cursor.execute("SELECT * FROM %s WHERE ROWNUM < 2" % self.connection.ops.quote_name(table_name)) + self.cache_bust_counter += 1 + cursor.execute("SELECT * FROM {} WHERE ROWNUM < 2 AND {} > 0".format( + self.connection.ops.quote_name(table_name), + self.cache_bust_counter)) description = [] for desc in cursor.description: name = force_text(desc[0]) # cx_Oracle always returns a 'str' on both Python 2 and 3 diff --git a/django/db/backends/oracle/schema.py b/django/db/backends/oracle/schema.py index fa710dc443..e4b02fcc7b 100644 --- a/django/db/backends/oracle/schema.py +++ b/django/db/backends/oracle/schema.py @@ -87,9 +87,6 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor): self.remove_field(model, old_field) # Rename the new field self.alter_field(model, new_temp_field, new_field) - # Close the connection to force cx_Oracle to get column types right - # on a new cursor - self.connection.close() def normalize_name(self, name): """ diff --git a/docs/releases/1.8.txt b/docs/releases/1.8.txt index bbb932ada3..4f77f063a3 100644 --- a/docs/releases/1.8.txt +++ b/docs/releases/1.8.txt @@ -286,6 +286,10 @@ Database backends * The MySQL backend no longer creates explicit indexes for foreign keys when using the InnoDB storage engine, as MySQL already creates them automatically. +* The Oracle backend no longer defines the ``connection_persists_old_columns`` + feature as ``True``. Instead, Oracle will now include a cache busting clause + when getting the description of a table. + Email ^^^^^