Here's my desired schema:

```
{
    username: "taimoor",
    pairs: [
        {
            code: "CA",
            site: "google.ca"
        },
        {
            code: "US",
            site: "google.com"
        },
        {
            code: "GB",
            site: "google.co.uk"
        }
    ]
    date: 1574880349,
}

```

Here's my current schema:

```
const redirectionSchema = new mongoose.Schema({
    username: {
        type: String,
        required: true,
    },
    pairs: [
        // What do I place here?
    ],
    date: {
        type: Date,
        required: true,
        default: Date.now
    }
})

```

I don't know how to proceed and implement this using `mongoose`. Should I create another schema called `Pair`? And if so:

* How do I ensure the pairs will be valid?
* How do I add a `Pair` to "pairs" programmatically?

Thanks for your time, this is my first time using NoSQL.