Though wouldn't mind 180 either. On Tue, Dec 29, 2015 at 2:55 PM, Collin Anderson <cmawebs...@gmail.com> wrote:
> I propose 150 to err on the longer side: > https://github.com/django/django/pull/5891 > > On Tuesday, December 29, 2015 at 5:28:01 AM UTC-5, Aymeric Augustin wrote: >> >> At that point, I'd prefer picking an arbitrary length that makes sense >> for the underlying data rather than one based on MySQL's current >> limitations. >> >> Name length sounds like an reasonable proxy for username length. A quick >> Google search turns up >> http://www.historyrundown.com/top-5-people-with-the-longest-names/ >> >> If we skip the pathological cases — e.g. people with one name per letter >> of the alphabet — the first sensible name in that list is Picasso with 122 >> characters: "Pablo Diego José Francisco de Paula Juan Nepomuceno María de >> los Remedios Cipriano de la Santísima Trinidad Ruiz y Picasso" >> >> The original ticket, #20846, discussed a length between 75 and 150. >> >> The argument for 254 was "email as username". In that case, Django's >> native User with distinct username and email fields isn't appropriate. A >> custom user model storing the the username/email in a unique EmailField is >> better. MySQL users can specify the appropriate max_length — which we >> should document — there. >> >> I'd jut give username max_length=120. (Sorry, Picasso.) >> >> -- >> Aymeric. >> >> >> 2015-12-28 23:49 GMT+01:00 Tim Graham <timog...@gmail.com>: >> >>> Ugh, I guess I'm in favor of max_length=191. It'll just be awkward to >>> explain that one in the docs. >>> >>> On Monday, December 28, 2015 at 3:27:23 PM UTC-5, Collin Anderson wrote: >>>> >>>> Hi All, >>>> >>>> I finally looked at this more today. I started working on the INDEX >>>> (col1(191)) solution from #18392, but unfortunately I don't think we can >>>> use that solution in this case because it's a UNIQUE index. (I still think >>>> it's best solution for non-unique indexes.) >>>> >>>> I think these are our options (in my humble order of preference), none >>>> of them ideal: >>>> 1. Make username max_length=191 or some other nice number less 191. >>>> 2. Revert completely back to username max_length=30 >>>> 3. Tell mysql folks they can only use the insecure[1] version of utf8 >>>> unless do some really complex reconfiguration (see "Hardest" solution in >>>> the article [2]) to get utfmb4 support. Based on the fact that they're >>>> using mysql and not PostgreSQL in the first place, many mysql users are >>>> probably are unable to make the needed changes. >>>> >>>> The good news is that mysql 5.7.7 (which, will _start_ to get a lot of >>>> real use in 16.04) changes some defaults[3] to make the "hardest" solution >>>> easier (just need to set ROW_FORMAT=DYNAMIC). MariaDB hasn't changed the >>>> default [4]. I hope they do before RHEL/CentOS 8. Even then it's a long >>>> wait before most people have it. >>>> >>>> Collin >>>> >>>> [1] https://youtu.be/qFfjJ8pOrWY?t=2534 >>>> [2] https://serversforhackers.com/mysql-utf8-and-indexing >>>> [3] http://bugs.mysql.com/bug.php?id=68453#c430229 >>>> [4] >>>> https://mariadb.com/kb/en/mariadb/xtradbinnodb-server-system-variables/#innodb_large_prefix >>>> >>>> >>>> >>>> On Mon, Dec 21, 2015 at 11:32 AM, Tim Graham <timog...@gmail.com> >>>> wrote: >>>> >>>>> I merged the often requested increase of User.username max_length to >>>>> 254 characters [1] a few weeks ago, however, the ticket was reopened >>>>> pointing out this issue: >>>>> >>>>> >>>>> "This patch breaks on MySQL installations using the utf8mb4 charset, >>>>> because it breaks the index length limit - it comes out at a maximum of >>>>> 254 >>>>> * 4 = 1016 bytes whilst by default InnoDB can only index 767 bytes. I >>>>> found >>>>> this because I am using utf8mb4 in django-mysql's tests. >>>>> >>>>> Django encourages using the utf8 charset (3 bytes per character - >>>>> cannot store emojis), although there has been some discussion for moving >>>>> to >>>>> utf8mb4 in #18392 <https://code.djangoproject.com/ticket/18392>. One >>>>> can index 254 character utf8mb4 fields in MySQL by using a couple settings >>>>> as described in that ticket, Django could enforce those, or the field >>>>> could >>>>> be changed to just 191 characters instead which is the maximum indexable >>>>> (767 >>>>> // 4)." >>>>> >>>>> Do we have any MySQL enthusiasts willing to champion a patch (or at >>>>> least a decision design about the best way to proceed) for #18392 [2] to >>>>> resolve this? >>>>> >>>>> [1] https://code.djangoproject.com/ticket/20846 >>>>> [2] https://code.djangoproject.com/ticket/18392 >>>>> >>>>> -- >>>>> 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 post to this group, send email to django-d...@googlegroups.com. >>>>> Visit this group at https://groups.google.com/group/django-developers. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/django-developers/ceb190b5-5218-446c-a6a0-0aea75e7fd6b%40googlegroups.com >>>>> <https://groups.google.com/d/msgid/django-developers/ceb190b5-5218-446c-a6a0-0aea75e7fd6b%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 django-develop...@googlegroups.com. >>> To post to this group, send email to django-d...@googlegroups.com. >>> Visit this group at https://groups.google.com/group/django-developers. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/django-developers/78e114b4-9595-484a-bc33-f87635a2e7c0%40googlegroups.com >>> <https://groups.google.com/d/msgid/django-developers/78e114b4-9595-484a-bc33-f87635a2e7c0%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 django-developers+unsubscr...@googlegroups.com. > To post to this group, send email to django-developers@googlegroups.com. > Visit this group at https://groups.google.com/group/django-developers. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-developers/ae4782fd-0f78-4b8a-9a94-af987e07e400%40googlegroups.com > <https://groups.google.com/d/msgid/django-developers/ae4782fd-0f78-4b8a-9a94-af987e07e400%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. 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