firebase-write.js

// Firebase V3.0.0
// an example using a single atomic `update()` to create objects in three 'tables' that reference each other.
// one school has many courses and many studens
// one course has many students and is in only one school
// one student is in many courses and only one school

db = firebase.database().ref('test');

const userId = firebase.auth().currentUser.uid;

const school1Key = db.child('data/schools').push().key;
const course1Key = db.child('data/courses').push().key;
const course2Key = db.child('data/courses').push().key;
const student1Key = db.child('data/students').push().key;
const student2Key = db.child('data/students').push().key;

const school1 = {
    name: 'A magnificent school',
    courseKeys: {
        [course1Key]: true,
        [course2Key]: true,
    },
    studentKeys: {
        [student1Key]: true,
        [student2Key]: true,
    },
};

const course1 = {
    name: 'An excellent course',
    schoolKey: school1Key,
    studentKeys: {
        [student1Key]: true,
        [student2Key]: true,
    },
};

const course2 = {
    name: 'An second excellent course',
    schoolKey: school1Key,
    studentKeys: {
        [student2Key]: true,
    },
};

const student1 = {
    name: 'Bobby Brown',
    schoolKey: school1Key,
    courseKeys: {
        [course1Key]: true,
    },
};

const student2 = {
    name: 'Sally Mae',
    schoolKey: school1Key,
    courseKeys: {
        [course1Key]: true,
        [course2Key]: true,
    },
};

const newData = {
    [`users/${userId}/schoolKeys/${school1Key}`]: true,
    [`users/${userId}/mruSchool`]: school1Key,
    [`users/${userId}/courseKeys/${course1Key}`]: true,
    [`users/${userId}/courseKeys/${course2Key}`]: true,
    [`users/${userId}/studentKeys/${student1Key}`]: true,
    [`users/${userId}/studentKeys/${student2Key}`]: true,
    [`data/schools/${school1Key}`]: school1,
    [`data/courses/${course1Key}`]: course1,
    [`data/courses/${course2Key}`]: course2,
    [`data/students/${student1Key}`]: student1,
    [`data/students/${student2Key}`]: student2,
};

db.update(newData);