I’m working on a ruby on rails project that requires recording some simple user data which fits in a many-to-many relationship (think of it as an set of user interests). I’m experienced with doing many to many relations using has_many :through and HABTM, but when the thing is simple enough that it could be represented as a single word it seems like overkill to create a new model and to have to do the required joins to access it. I don’t see much need in recording other properties than the name of the interest itself, so that argument for using a model isn’t persuasive. I know noSQL can be good for this, but I’m wondering what the right way to do this with a relational db would be (I’m using postgres), both from a performance and good design perspective. The approach I’m thinking of using would be to record it as a delimited string in the user model using the text datatype and then parse this into an array. or this could be a string representing an array of hash keys which then queries a hash table or key/value store db for the data. I’m sure there many different approaches to this, but I’d appreciate knowing what the best practice would be, since I expect I’ll be having to implement this in the future a lot. Also if you could recommend any any tools/gems/frameworks that assist in this that would be very helpful.
Thank you.
Basically serialize the data in some way and store it in a column knowing in advance that you will not query against it. One fairly compact solution I’ve seen people use is to store it as json which relieves you of having to do anything complicated. You simply need a varchar type that is large enough to store the json strings.