Hi Anshuman, As I mentioned when you raised this issue 2 days, ago:
https://groups.google.com/d/msgid/django-developers/bac70fe2-3bbb-45c9-b805-5469e89f2754%40googlegroups.com?utm_medium=email&utm_source=footer if you can provided evidence to back up your claim, I'll reverse my position on the need for an API entry point like the one you describe. However, as I said in that thread, the comparison shouldn't be "Update 1000 rows in 1 statement" vs "Update 1000 rows using 100 transactions" - it should be vs "update 1000 rows in a *single* transaction". Using 1000 *transactions* will clearly be slower, but my gut tells me that 1000 individual SQL statements, amalgamated into a single transaction, should be just as efficient as a single large statement - or, at least, that the difference in performance will be sufficiently small as to be ignorable. You're not going to advance your cause by starting a new thread every couple of days until someone agrees with you. I've given you a specific course of action - provide performance benchmarks. Until you provide them, the only thing reposting like this will do is annoy the people you need to help you. Yours, Russ Magee %-) On Mon, Oct 20, 2014 at 1:22 PM, Anshuman Aggarwal < [email protected]> wrote: > Posting this Django Project ticket that I opened to track the enhancement > request to update multiple rows with different values for the same field > for a particular Django queryset in a single SQL query without having to > write raw SQL. Please see the discussion there. > > https://code.djangoproject.com/ticket/23646 > > I disagree with Russel that there will not be a performance impact. Firing > 1000s of SQL queries to update single rows will lead to locking of the > table in Postgres atleast, not to mention the overheads of individual SQL > queries, transactions etc. If the database support natively updating > multiple values then it can be done that way. > > > A possible SQL solution is outlined in the link (below) but it should > ideally be supported via the Django Manager and not via a Raw SQL which > becomes much harder to maintain. > > http://stackoverflow.com/questions/18797608/update-multiple-rows-in-same-query-using-postgresql > > If agreed, I would look to contributing a patch if we can finalize the API > for the same here. > > Thanks, > Anshuman > > -- > 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 [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/django-developers. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-developers/c650999b-7a0d-49e8-aa0d-84e789b2f833%40googlegroups.com > <https://groups.google.com/d/msgid/django-developers/c650999b-7a0d-49e8-aa0d-84e789b2f833%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/django-developers. To view this discussion on the web visit https://groups.google.com/d/msgid/django-developers/CAJxq84-ZRUqgoCrdH9ORU5gxhD4WMSU64orrw9nfKwfkzXDGYg%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
