René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Queries with null don't work as expected","articleBody":"### Version info\r\n\r\n**Angular:** 2.2.3\r\n\r\n**Firebase:** 3.6.1\r\n\r\n**AngularFire:** 2.0.0-beta.6\r\n\r\n\r\n### How to reproduce these conditions\r\n\r\nStackoverflow: [AngularFire2: query if child exists](http://stackoverflow.com/questions/40359007/angularfire2-query-if-child-exists)\r\n\r\nFirebase Google Group: [AngularFire2 query with null doesn't work](https://groups.google.com/forum/#!topic/firebase-talk/zTjrOwqxrI0)\r\n\r\n**Steps to set up and reproduce** **Sample data and security rules**\r\n\r\nSee Stackoverflow question above. \r\n\r\n### Expected behavior\r\n\r\nQueries with given `ordeByChild: \"property\"` and `endAt : null` is expected to filter out lists where those poperties are null/don't exist. \r\n\r\n### Actual behavior\r\n\r\nWhole list is returned with no filtering.\r\n\r\nAs @cartant pointed out, check [could be done here](https://github.com/angular/angularfire2/blob/2.0.0-beta.6/src/database/query_observable.ts#L195-L197) just against `undefined` maybe and not to `null`.\r\n","author":{"url":"https://github.com/bogacg","@type":"Person","name":"bogacg"},"datePublished":"2016-11-30T08:50:12.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":13},"url":"https://github.com/704/angularfire/issues/704"}