PostgreSQL jsonb field in ActiveRecord belongs_to association

问题

Can I use a jsonb field as a foreign_key in a belongs_to association? Something along the lines of:

belongs_to :product, class_name: "Product",  foreign_key: "data ->'product_id'"

回答1:

References can be defined only between columns (or groups of columns), as it is stated in the documentation:

FOREIGN KEY ( column_name [, ... ] ) REFERENCES reftable [ ( refcolumn [, ... ] ) ]

回答2:

you can use activerecord-json-associations to use PostgreSQL JSONB fields to store association information of your models

来源：https://stackoverflow.com/questions/32889252/postgresql-jsonb-field-in-activerecord-belongs-to-association