Rails way to query on array inside JSON data type -

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i have column in table json data type storing array.

migration

class addeditsummarytoposts < activerecord::migration   def change     add_column :posts, :edit_summary, :json   end end

post

class post < activerecord::base   serialize :edit_summary, json end

this how data stored:

:id => 2, :edit_summary => [   {     "user_id" => 56,     "date" => "2016-08-09t07:46:04.555-04:00"   },   {     "user_id" => 57,     "date" => "2016-08-08t06:35:44.345-04:00"   }, ]

i referred this post , wrote query working fine

select *   posts, json_array_elements(edit_summary) elem  elem->>'date' between '2016-08-07 00:00:00' , '2016-08-10 23:59:59';

now question there way same rails way?

you can execute same query in rails providing raw sql conditions.

however, feel edit summaries belong relation instead.

a post has_many editsummary, benefits:

  • you'll able index dates , fk's.
  • db consistency (there's nothing preventing user_id being invalid id).
  • separation
  • db validation

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