[All codes here are samples] I have the Book model with the info field as hstore.
class Book < ActiveRecord::Base
serialize :info, ActiveRecord::Coders::NestedHstore
end
and the info field is filled like this:
info: {"tags" => ["tag one", "tag two"]}
I need a query that I can find the books that contains the tag "tag one". How can I accomplish this?
You might not want to use a a hstore column here at all. Since hstore stores the values as plain text you need to do something like:
Book.where("WHERE info->'tags' LIKE '%?%'", "bestseller");
Seems like a decent idea until you realize that you are doing a full text search on a comma delimited string.
Instead you might want to use a tags table and a book_tags join table the good old way.
hstore is great for key/value data but it does not automatically turn Postgres into Mongodb. If you are shoving serialized data into a hstore than you should most likely be using a relation instead.