django - “select_for_update” 在原子 block 内调用仍然 TransactionManagementError

Question

代码崩溃

@transaction.atomic
def cancel_one(o_id):
    order= Order.objects.select_for_update().get(id=o_id)

加注

TransactionManagementError('select_for_update cannot be used outside of a transaction.')

django.db.transaction.TransactionManagementError: select_for_update cannot be used outside of a transaction.

我已通过 transaction.get_connection().in_atomic_block 检查了我的代码是否在事务中。

它出现在交易中，但仍然引发

Error: django.db.transaction.TransactionManagementError: select_for_update cannot be used outside of a transaction.

我的代码:

# Step1
def cancel_one(o_id):
   print("DO")
   cxn = transaction.get_connection()
   if cxn.in_atomic_block:
       print("We're inside a transaction!")
   order= Order.objects.select_for_update().get(id=o_id)

# Step2
@transaction.atomic
def cancel_one(o_id):
   print("DO")
   cxn = transaction.get_connection()
   if cxn.in_atomic_block:
       print("We're inside a transaction!")
   order= Order.objects.select_for_update().get(id=o_id)

代码结果

# Step1
-----------------------
DO
-----------------------

# Step2
-----------------------
DO
"We're inside a transaction!"
-----------------------

Answer 1

您是否有机会使用 DBRouters？我遇到了麻烦-技巧是在事务和 select_for_update 上定义数据库

with transaction.atomic(using='db_x'):
    order = Order.objects.using('db_x').select_for_update().get(id=o_id)