Re: [Sqlalchemy-tickets] [sqlalchemy] #2861: document use of version_id_col with versioning example
Brought to you by:
zzzeek
|
From: sqlalchemy <mi...@zz...> - 2013-11-08 23:21:11
|
#2861: document use of version_id_col with versioning example
--------------------------------+-----------------------------------
Reporter: bikbit | Owner: zzzeek
Type: defect | Status: new
Priority: medium | Milestone: 0.9.0
Component: documentation | Severity: trivial - <10 minutes
Resolution: | Keywords: versioning
Progress State: in queue |
--------------------------------+-----------------------------------
Changes (by zzzeek):
* milestone: 0.8.xx => 0.9.0
* component: utils => documentation
* severity: very major - up to 2 days => trivial - <10 minutes
* status_field: awaiting triage => in queue
Comment:
sure, this is a natural effect of the two transactions not being entirely
isolated. If you have your isolation set at at least REPEATABLE READ then
you wouldn't get this issue.
you can alleviate this condition using a different kind of "versioning"
which is the mapper-level versioning feature, see
http://docs.sqlalchemy.org/en/rel_0_9/orm/mapper_config.html#configuring-a
-version-counter.
I've committed a proof of concept for this in rac54ba0f2d8df5a76b685284.
A change could be to make this a flag on the `Versioned` class itself and
to add documentation.
--
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/2861#comment:1>
sqlalchemy <http://www.sqlalchemy.org/>
The Database Toolkit for Python
|