For example,

• check whether an id is an integer or
• (if using Vuex store), check and verify whether id exists and matches with the value in database.

Let's take an example of 'users' data we've been working with. Create dynamic route in /pages directory, and call it _id.vue

** For validate hook to work, it must return true or false to trigger next steps. If nothing is returned, validation fails by default.**

// pages/_id.vue

export default {
    validate({ params, query, store }) {
        console.log("Validate hook called from dynamic route");
        let user = store.state.users.find(obj => {
            return obj.id == params.id;
        });
        return user ? true : false;
    }
};