On 11/30/2015 12:54 PM, Alyssa Kwan wrote: > Hi, > > The problem I'm trying to solve is I've created a multi-temporal > relational table construct (à la bitemporality) that I want to create > SQLAlchemy Core composite operations for (and eventually SQLAlchemy ORM). > > Let's call these TemporalRelationSet's. I've subclassed SchemaItem.
I'd not do that. If the thing you're dealing with is a Table, use Table. If you want to define a bunch of special operations involving a certain Table and you're not able to use ORM, make a TemporalRelationSet of course, however, this is not a schema item. It would refer to the Table you're dealing with. That is, prefer composition over inheritance. A SchemaItem is only intended to be the base of objects that exist concretely within DDL. I > also do registration against a Registry class that I've subclassed > MetaData for, with a __visit_name__ of 'registry'. The idea is that I > initialize a Registry, can register Table's against it, as well as these > TemporalRelationSet's. When your TemporalRelationSet is created, it can put memos inside of Table.info for its Table object; if you want things to happen when that Table gets created, you can use the before_create / after_create event listeners to handle this. > > Does this make sense for what I'm trying to do? > > If so, the specific problem I'm running into is create_all() on Registry > doesn't do anything. I started digging into the Visitable metaclass, but > hit a wall of understanding. Stick to the event API here, see the overview at http://docs.sqlalchemy.org/en/latest/core/events.html?highlight=after_create#schema-events. > > I'm running Python 3.4.3 on OS X El Capitan with SQLAlchemy 1.0.9. > > Thanks! > Alyssa > > -- > You received this message because you are subscribed to the Google > Groups "sqlalchemy" group. > To unsubscribe from this group and stop receiving emails from it, send > an email to sqlalchemy+unsubscr...@googlegroups.com > <mailto:sqlalchemy+unsubscr...@googlegroups.com>. > To post to this group, send email to sqlalchemy@googlegroups.com > <mailto:sqlalchemy@googlegroups.com>. > Visit this group at http://groups.google.com/group/sqlalchemy. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
