ah the example has a bug, you're hitting a second part of the code there where
it fetches columns that are placed on a single table child class that are moved
up to the parent. Committing this now, here's a patch:
diff -r 653ae7f17379 examples/versioning/history_meta.py
--- a/examples/versioni
Hello!
I've run into an odd error whilst using the history meta. I've got a
class which has two sub classes which define some additional columns.
The MainMeter class has a unique constraint on one of the colums.
When I have the history_meta create my history tables, the
trading_point_name column
