On Mon, Jul 8, 2013 at 2:52 AM, Ethan Furman <et...@stoneleaf.us> wrote:
> On 07/07/2013 06:43 AM, Chris Angelico wrote:
>>
>> On Sun, Jul 7, 2013 at 11:13 PM, Wayne Werner <wa...@waynewerner.com>
>> wrote:
>>>
>>> Which you would then use like:
>>>
>>>
>>> conn = create_conn()
>>> with new_transaction(conn) as tran:
>>> rows_affected = do_query_stuff(tran)
>>> if rows_affected == 42:
>>> tran.commit()
>>
>>
>> Yep. There's a problem, though, when you bring in subtransactions. The
>> logic wants to be like this:
>
>
> Is there some reason you can't simply do this?
>
> with new_transaction(conn) as tran1:
> tran1.query("blah")
> with tran1.subtransaction() as tran2:
> tran2.query("blah")
> with tran2.subtransaction() as tran3:
> tran3.query("blah")
>
> # roll this subtransaction back
> tran2.query("blah")
> tran2.commit()
> tran1.query("blah")
> tran1.commit()
That means that I, as programmer, have to keep track of the nesting
level of subtransactions. Extremely ugly. A line of code can't be
moved around without first checking which transaction object to work
with.
ChrisA
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