How to add an element into an array of a Serialize Field using Ruby on Rails

Question

I have a field call query_data defined as text in my MySQL database. In my model I defined this field as serialize :query_data, JSON. The JSON format I would like to save and retrieve look like that: {:items => [ {:id => 1}, {:id => 2}, {:id => 3} ]} I have a collection (in that case, called items) that contain an array of objects. I was wondering, what's the best way to add or delete an Item. Ex: remove {:id => 2} from my items list and add `{:id => 4} to it JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

Ruby on Rails has some nice methods to move seamlessly between JSON and Ruby. thing = {:items => [ {:id => 1}, {:id => 2}, {:id => 3} ]} thing.to_json # "{\"items\":[{\"id\":1},{\"id\":2},{\"id\":3}]}" thing.to_json is essentially what's happening in the serializer. If you want them back to Ruby, you can just do: @items = @thing.query_data JSON.parse(@items) # "items"=>[{"id"=>1}, {"id"=>2}, {"id"=>3}]} Now that we can easily move between the two, lets just use Ruby syntax to deal with adding and deleting keys. thing = {:items => [ {:id => 1}, {:id => 2}, {:id => 3} ]} thing[:items] = thing[:items].append({:id => 4}) # adding a new item thing[:items] = thing[:items].select { |item| item[:id] != 2 } # removing an item