Firebase crud operations improper documentations



there are no such examples templates for crud…

if i put this in app.js

    databaseURL: "",
    apiKey: "AIzaSyD3FKLpiV-bOGwFsCb-_q6gpyufrc5Uk6A",
    authDomain: "",
    storageBucket: ""

      function (instance) {
        console.log("firebase.init done");
      function (error) {
        console.log("firebase.init error: " + error);

ill get

Error: java.lang.IllegalArgumentException: The storage Uri could not be parsed.
System.err: Source)

after removing storage bucket app starts well, but in viewmodel if i put this.
var database = firebase.database();
ill get

firebase.database is not a function

any docs for crud operations in firebase ?