I'm trying to weaken a sql unique constraint.
Let's say I have a Human model with name and gender fields. And the name must be unique.

sql_constraints = [('name_unique', UNIQUE(name), 'Error: Name must be unique!')]

What I want is, that the name has to be unique if the gender is female.
How to achieve that?

Can I do something like:

sql_constraints = [('human_check', CHECK(gender='female' AND UNIQUE(name) OR (gender='male'), 'Error: Females must have unique names!')]

Or should I write a custom constraint?
Any other suggestions? (Like splitting the model into Males and Females)

Thanks.