That's a great idea, actually. Thank you On Wednesday, June 1, 2022 at 4:56:31 PM UTC+3 Adam Johnson wrote:
> Modifying the connections object seems like the wrong way to approach > this, as it's not intended for mutation. Did you consider writing a > database router and then having a context manager that affects the router's > state? > https://docs.djangoproject.com/en/4.0/topics/db/multi-db/#topics-db-multi-db-routing > > . That is the API Django supports for moving queries to different databases. > > On Wed, Jun 1, 2022 at 2:21 PM Alexander Lyabah <a.ly...@checkio.org> > wrote: > >> In some of the previous version on Django I had a very useful context >> manager. >> >> from contextlib import ContextDecorator >> from django.db import connections >> >> class overwrite_default_connection(ContextDecorator): >> prev_default = None >> write_connection = None >> >> def __init__(self, write_connection): >> self.write_connection = write_connection >> >> def __enter__(self): >> self.prev_default = connections['default'] >> connections['default'] = connections[self.write_connection] >> return self >> >> def __exit__(self, *exc): >> connections['default'] = self.prev_default >> return False >> >> Which allows me to overwrite default connection. It is very useful when >> you use a jupyter notebook and you need to switch between db connections >> that have different data but the same structure (django models) >> >> But the shared implementation of that context manager stops working >> recently >> >> ValueError: Subqueries aren't allowed across different databases. Force >> the inner query to be evaluated using `list(inner_query)`. >> >> But I'm wondering wouldn't it be useful to have that kind of manager in >> the core Django functionality, or it is a stupid idea? >> >> Thank you >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Django developers (Contributions to Django itself)" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to django-develop...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/django-developers/ad453105-2116-40c9-a1ff-9571bfb080d1n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/django-developers/ad453105-2116-40c9-a1ff-9571bfb080d1n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "Django developers (Contributions to Django itself)" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-developers+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/django-developers/cbe7f3b8-0f8b-49c3-b3e8-7c58fe612c90n%40googlegroups.com.
