如何设置rails验证列hstore键的唯一性？

Question

I have a table channels , with an hstore column credentials . The credentials for each channel might be different, but I want them to be unique when populated. I have set some postgres indexes like this:

execute "CREATE UNIQUE INDEX channels_key_seller_id_values_unique ON channels((credentials -> 'seller_id'))"
execute "CREATE UNIQUE INDEX channels_key_auth_token_values_unique ON channels((credentials -> 'auth_token'))"

This correctly raises a hard error during @channel.save with ActiveRecord::RecordNotUnique , however I would like the familiar rails way of displaying form errors. What (if any) is the syntax of using validates uniqueness on hstore keys 'auth_token' and 'seller_id' ?

Answer 1

Check this, it might help: https://gist.github.com/rf-/2322543

Notice that he used 'sqlite3'.