> How many times have you worked on a project and, after 1-2 years of development, you have changed to a different database? > > > I can tell you how many times it happened to me, I counted them: exactly never.

I guess this is the crux.

You hardly know in advance this is going to happen.

I experienced this transition (mysql>pgsql), though not with Django.

The ORM was perfect. If I recall correctly, only the customized SQL queries (only a few present) had to br adapted, everything else just worked.

11/10 would chose such a framework again.