Proper NoSQL data schema for web photo gallery

Question

I\'m looking to build an appropriate data structure for NoSQL storage of a photo gallery. In my web application, a photo can be part of 1 or more albums. I have experience with

Answer 1

Using mongodb lingo, your collections could look like this:

photos = [
    {
        _id: ObjectId(...),
        title: "...",
        date_uploaded: Date(...),
        albums: [
            ObjectId(...),
            ...
        ]
    },
    ...
]

albums = [
    {
        _id: ObjectId(...),
        title: "..."
    }
]

Finding the 5 newest photos would be done like this:

> var latest = db.photos.find({}).sort({date_uploaded:1}).limit(5);

There's no server-side joins in mongo, so you'd have to fetch all the latest albums like this:

> var latest_albums = latest.find({}, {albums: 1});

Of course, then you have to boil this down into a set.

It's actually easier if you just embed the album inside the photo documents, since they're small:

photos = [
    {
        _id: ObjectId(...),
        title: "...",
        date_uploaded: Date(...),
        albums: [
            {name: "family-vacation-2011", title: "My family vacation in 2010"},
            ...
        ]
    },
    ...
]

Then querying is the same, but you don't have to join. Finding all photos in an album looks like:

> db.photos.find({albums:{$elemMatch:{name: "family-vacation-2011"}}});