Fixed #29103 -- Removed bad 'b'-prefix added by MySQL's SchemaEditor.quote_value().

django/db/backends/mysql/schema.py

@@ -25,9 +25,11 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
     sql_delete_pk = "ALTER TABLE %(table)s DROP PRIMARY KEY"
 
     def quote_value(self, value):
-        # Inner import to allow module to fail to load gracefully
-        import MySQLdb.converters
-        return MySQLdb.escape(value, MySQLdb.converters.conversions)
+        self.connection.ensure_connection()
+        quoted = self.connection.connection.escape(value, self.connection.connection.encoders)
+        if isinstance(value, str):
+            quoted = quoted.decode()
+        return quoted
 
     def _is_limited_data_type(self, field):
         db_type = field.db_type(self.connection)

tests/backends/mysql/test_schema.py

@@ -9,6 +9,7 @@ class SchemaEditorTests(TestCase):
     def test_quote_value(self):
         editor = connection.schema_editor()
         tested_values = [
+            ('string', "'string'"),
             (42, '42'),
             (1.754, '1.754'),
             (False, '0'),

tests/schema/test_logging.py

 from django.db import connection
-from django.test import SimpleTestCase
+from django.test import TestCase
 from django.test.utils import patch_logger
 
 
-class SchemaLoggerTests(SimpleTestCase):
+class SchemaLoggerTests(TestCase):
 
     def test_extra_args(self):
         editor = connection.schema_editor(collect_sql=True)