[odb-users] postgres constraints (or triggers)

[MM]

Hello,

I wish to ensure that the sum of a column across all rows always equals
100%.
Currently I ensure that at the application level before persistence.
postgresql CHECK constraint doesn't work for this but I believe a TRIGGER
may work before insert/update.
There's no odb support for that is there?  Is it the advice to keep at user
code in the application instead?