id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
2227	transaction.commit()/rollback() should be aware of nested calls to transaction.managed(True)	mderk@…	Aymeric Augustin	"As I see in the transaction.py, commit()/rollback() call connection._commit()/connection._rollback() explicitly. 
It breaks the case when a function with commit_manually or commit_on_success decorator calls another function decorated the same way (enters the transaction management).

Consider following scenario:
{{{
# a bank account class
class Account:
    @transaction.commit_on_success
    def withdraw(self, sum):
    # code to withdraw money from the account 

    @transaction.commit_on_success
    def add(self, sum):
    # code to add money to the account

# somewhere else
@transaction.commit_on_success
def makeMoneyTransaction(from_account, to_account, sum):
    # this code will call commit on success
    from_account.withdraw(sum)

    # this code may raise an exception, and if it raises, 
    # commit won't be called in Account.add() and makeMoneyTransaction()
    # But money had been already withdrawn, and the from_account saved in the database.
    # The makeMoneyTransaction's transaction is inconsistent.
    # So we loose our money
    to_account.add(sum)

}}}

IMO, what the transaction.commit should do in this case is to check first whether the transaction is ""nested"". 
In the [http://adodb.sourceforge.net/ AdoDB] PHP library, each call to StartTrans either starts new transaction or increments the counter of the nested StartTrans calls. CompleteTrans either calls commit/rollback (if its StartTrans counterpart was not called inside another StartTrans/CompleteTrans block) or decrements the counter.
I rate this deficiency as major. What do you think?"	New feature	closed	Database layer (models, ORM)	dev	Normal	fixed	transaction, nest, scope, nested, rollback, commit	md@… research@… hv@… aball@… Forest Bond Walter Doekes Dave Hall vlastimil.zima@… Steve Jalim ionel.mc@… mmitar@…	Accepted	1	0	0	1	0	0