If not I'am wrong, postgresql uses "read commited" by default and mysql "repeatable read"
http://www.postgresql.org/docs/9.1/static/transaction-iso.html -> "Read Committed is the default isolation level in PostgreSQL. " http://dev.mysql.com/doc/refman/5.0/en/innodb-transaction-model.html -> "In terms of the SQL:1992 transaction isolation levels, the default InnoDB level is REPEATABLE READ. InnoDB" Andrey 2013/3/4 Aymeric Augustin <[email protected]> > On 4 mars 2013, at 04:04, Shai Berger <[email protected]> wrote: > > > you need to be sure that, in all these places, either reads don't > > really affect consequent writes, or some constraint holds that is > equivalent to > > serializability -- otherwise, negative effect is possible. > > PostgreSQL and Oracle use the "repeatable read" isolation level by > default. They are > immune to this problem, because a sequence of reads followed by a write > has the same > semantics with a transaction under "read committed" and without a > transaction. > > MySQL uses "read committed" and SQLite uses "serializable". Users of these > databases > may see a different behavior. > > I'm going to add this to the list of backwards incompatibilities: > > https://github.com/aaugustin/django/commit/876fddb68dd6990e87b15e683c498e41f8921f14#L4R437 > ("Using unsupported database features" isn't correct for MySQL and SQLite > right now.) > > Let me know if you think of other cases which I haven't covered! > > -- > Aymeric. > > -- > You received this message because you are subscribed to the Google Groups > "Django developers" 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?hl=en > . > For more options, visit https://groups.google.com/groups/opt_out. > > > -- Andrey Antukh - Андрей Антух - <[email protected]> http://www.niwi.be/about.html http://www.kaleidos.net/A5694F/ "Linux is for people who hate Windows, BSD is for people who love UNIX" "Social Engineer -> Because there is no patch for human stupidity" -- You received this message because you are subscribed to the Google Groups "Django developers" 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?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
