Adrian von Bidder wrote: > Heyho! > > [multi-column primary key where one column is autoincrement int] > > On Wednesday 16 December 2009 05.29:54 Daniel Falk wrote: >> The true problem here >> is with sqlite, which tries to make a "smart" choice about whether to >> autoincrement or not. And it gets it wrong. SQLAlchemy is correct to >> not specify the id field in the INSERT statement. That's the cue to the >> db that it needs to supply that value on its own. > > Hmm. > > Closer inspection shows that > * sqlite doesn't even support the scenario I want (autoincrement on one > column with multi column primary key) and > * sqlalchemy doesn't notice this and just creates a two column primary > key > without autoincrement at all. > > Is there any hope that sqlalchemy will start to simulate the feature on > sqlite? (I'm using the python-pysqlite2 2.5.5-3 / libsqlite3-0 3.6.20-1 / > python-sqlalchemy 0.5.6-1 packages from Debian squeeze, btw) > > I've opened #1642 now.
Sorry, I've closed it. SQLite doesn't support autoincrement on composite PKs and theres no one-size-fits-all way to "simulate" this, so its up to the user. You need to either use the "default" keyword and specify a function or SQL expression that will generate new identifiers, or just set up the PK attributes on your new objects before adding them to the session. > > PostgreSQL handles this in just the way I was expecting (no surprise since > my expectation on autoincrement columns is derived from the way pg builds > its serial data type :-), so I'll have to test if sqlalchemy will do the > right thing here. Then I can at least use pg (I was planning to do so in > production anyway; sqlite is convenient for development though.) absolutely, PG uses sequences and has no issue here. the no-autoincrement-sqlite thing is an only-sqlite issue and we also have some unit tests that specifically skip sqlite for this reason. > > > cheers > -- vbi > > -- > featured product: GNU Privacy Guard - http://gnupg.org > -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalch...@googlegroups.com. To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en.
