mirrors/django
1
0
Fork 0
mirror of https://github.com/django/django.git synced 2025-10-27 23:56:08 +00:00
Code Issues 32 Releases Wiki Activity

Refs #27683 -- Allowed setting isolation level in DATABASES ['OPTIONS'] on MySQL.

Browse Source
This commit is contained in:
Tim Graham
2017-01-17 11:16:15 -05:00
committed by GitHub
parent 46e0335583
commit f01ad1cb6a
4 changed files with 113 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

42
django/db/backends/mysql/base.py
View File

@@ -219,6 +219,13 @@ class DatabaseWrapper(BaseDatabaseWrapper):
'iendswith': "LIKE CONCAT('%%', {})",
}
isolation_levels = {
'read uncommitted',
'read committed',
'repeatable read',
'serializable',
}
Database = Database
SchemaEditorClass = DatabaseSchemaEditor
# Classes instantiated in __init__().
@@ -252,7 +259,23 @@ class DatabaseWrapper(BaseDatabaseWrapper):
# We need the number of potentially affected rows after an
# "UPDATE", not the number of changed rows.
kwargs['client_flag'] = CLIENT.FOUND_ROWS
kwargs.update(settings_dict['OPTIONS'])
# Validate the transaction isolation level, if specified.
options = settings_dict['OPTIONS'].copy()
isolation_level = options.pop('isolation_level', None)
if isolation_level:
isolation_level = isolation_level.lower()
if isolation_level not in self.isolation_levels:
raise ImproperlyConfigured(
"Invalid transaction isolation level '%s' specified.\n"
"Use one of %s, or None." % (
isolation_level,
', '.join("'%s'" % s for s in sorted(self.isolation_levels))
))
# The variable assignment form of setting transaction isolation
# levels will be used, e.g. "set tx_isolation='repeatable-read'".
isolation_level = isolation_level.replace(' ', '-')
self.isolation_level = isolation_level
kwargs.update(options)
return kwargs
def get_new_connection(self, conn_params):
@@ -262,13 +285,20 @@ class DatabaseWrapper(BaseDatabaseWrapper):
return conn
def init_connection_state(self):
assignments = []
if self.features.is_sql_auto_is_null_enabled:
# SQL_AUTO_IS_NULL controls whether an AUTO_INCREMENT column on
# a recently inserted row will return when the field is tested
# for NULL. Disabling this brings this aspect of MySQL in line
# with SQL standards.
assignments.append('SQL_AUTO_IS_NULL = 0')
if self.isolation_level:
assignments.append("TX_ISOLATION = '%s'" % self.isolation_level)
if assignments:
with self.cursor() as cursor:
# SQL_AUTO_IS_NULL controls whether an AUTO_INCREMENT column on
# a recently inserted row will return when the field is tested
# for NULL. Disabling this brings this aspect of MySQL in line
# with SQL standards.
cursor.execute('SET SQL_AUTO_IS_NULL = 0')
cursor.execute('SET ' + ', '.join(assignments))
def create_cursor(self, name=None):
cursor = self.connection.cursor()