postgresql - Self joins in rails through array field on other model -

we have 2 postgresql tables follows:

keywords table: id, keyword (string) joins table: id, keyword_ids (integers array) 

now, want add associations both keywords , aliases model follows

class keyword < activerecord::base    has_many :joins end  class join < activerecord::base    belongs_to :keywords foreign_key: 'keyword_ids' end 

how can in rails 4 , postgresql 9.3?

it seems can't done rails associations, did following model/class method

def alias_keywords   aliaskeyword.select("keyword").joins("join alias_joins on alias_keywords.id = any(alias_joins.joins)").where("? = any(alias_joins.joins)", self.id).map{|x| x.keyword} end 

now, can easily, access aliaskeywords.first.alias_keywords