how to use jsonb in rails

Question

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?

score 7 · Answer 1 · answered Dec 24 '14 at 01:56

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

will this delete the data? – coderVishal Feb 07 '16 at 10:29 — coderVishal, Feb 07 '16 at 10:29
This does not delete the data. It converts json to jsonb. – Robert Feb 08 '16 at 17:34 — Robert, Feb 08 '16 at 17:34

score 4 · Accepted Answer · answered Dec 29 '14 at 09:13

4

Here is it how it worked with Rails 4.2

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

The answer above threw errors for me.

answered Dec 29 '14 at 09:13

Aravind

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Can you post your error? I ran that migration up and down to confirm it was working for me. – Robert Dec 30 '14 at 13:59
1

@Robert The error was something like unable to cast string to json or something like that. – Aravind Dec 30 '14 at 14:27
My migration only works for json to jsonb. Was your field a string - not json? – Robert Dec 30 '14 at 16:17
It was a json but did not work so I ended up doing what I did – Aravind Dec 30 '14 at 16:57

how to use jsonb in rails

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