how to use jsonb in rails

问题

I have a rails project with Postgresql 9.4 as backend. I have column like this:

t.json :slot_details, null: false, default: {}

How do I change this to JSONB from JSON? Should I add index and that will be changed to JSONB?

回答1:

For migrating this, you can do the following. Payload in this case was originally a json field.

  class AlterJsonbToJsonAndBack < ActiveRecord::Migration                      
    def up                                                                     
      change_column :dynamics, :payload, 'jsonb USING CAST(payload AS jsonb)'  
    end                                                                        

    def down                                                                   
      change_column :dynamics, :payload, 'json USING CAST(payload AS json)'    
    end                                                                        
  end                                                                          

To find out how to query jsonb in Rails 4.2, checkout this article

回答2:

Here is it how it worked with Rails 4.2

t.jsonb :slot_details, index: true, default: {}

The answer above threw errors for me.

来源：https://stackoverflow.com/questions/27343231/how-to-use-jsonb-in-rails