Hi everyone.
I’m going to use NoSQL database for a huge project but I’ve worked since 2002 with SQL databases so I’m quite “closed” about this kind of things.
I have a quite complex data tree and I’m wondering how to flat the data structure to make it work well and fast, even with millions of data loaded.
That’s the data part I’m worried about:
registered users can post things in the app. Latitude and longitude is saved into Firebase. A category and the creation data too.
Now.
I need to make a “query” like “SELECT * FROM posts WHERE category = {category} AND latitude > {latBig} AND latitude < {latSmall} AND (same for longitude) ORDER BY date DESC”
I know that I need to make indexes to make the JSON work well but I’m stuck here because there are lots of things to check.
My idea was to make posts as always, plus add an indexes of categories (they’re just 10 so it’s not so hard to make).
The user can filter things based on categories and/or position (posts near him) and THIS is the hard part.
QUESTION (finally):
How can I get just the last 100 created post near me of a specific category?
DOUBT:
Get all the posts based on data should be reeeeeeally heavy for the system or not?
In SQL less fetch data = more speed.
In NoSQL is that the same? Because I’ve read about no issue on getting so much data in a single call but It’s the opposite of what I’ve learned and used since now so I’m a little bit scared to make a complex app based on a service that I have to change in the future
Thanks for all the tips you’re going to tell me. It’s important for me to have all clear before touch a single line of code.
Thanks gensollen.
I’ve read all the Firebase blog, forum and documentation.
My needs are not only for the location. I need a way to do similar sql things in Firebase OR (and this one should be the solution) a new way to manage database data with NoSQL.
In this particular case I’ve done all the app and it was quite finished BUT It was a little bit slow and I need something better to manage all the data (but first of all FASTER). That’s why NoSQL.
Create “node” of the category, and but data in it. So you will do a geoquery in the node
var firebaseRef = new Firebase("https://<your-firebase>.firebaseio.com/THE_CATEGORY");
// Create a GeoFire index
var geoFire = new GeoFire(firebaseRef);
Thus you only query posts from the category and in the good location
I need to make the query I’ve wrote in the first post BUT “flatten” it to be used in Firebase’s NoSQL.
I need to understand if I fetch thousand of results and filter it (via AngularJS’s ngRepeat filter) is better than ask for a “complex” query to Firebase (plus I really don’t know IF it’s possible to ask for some deep search to Firebase).
The base of NoSQL is that you have to think about your query and you do not have to care about the data. You can have duplicate data (and you have to !). Query are then easier. But it is more difficult to change data ( cause you have different changes).
Thus I would create :
POSTS --> Category 1
–> Category 2
–> …
And then use geofire for querying in these categories
Does it make sense ?
You can fetch all the post and then filter them in your app, but you will download a lot of data, and it is not really scalable. Thus, you cannot really do a complex query, but you can do a complex structure in firebase, and then have simple query.
That’s the clue I’m right now and you’ve get it. Thanks
I still need a “click” as I call it. It’s the “how I can make this all work as it should creating which data structure”.
I have, for example, the “all posts” page that must show all the post ordered by data and with a limit of 100 posts.
The example you’ve done it’s ok if you have to choose a category but if you’re not?
I’ve read all about NoSQL, that’s why I’m asking, because I can’t get how to certain things.
I get how to flatten data but I still don’t get how to filter it from the Firebase side.
SELECT * FROM posts ORDER BY data DESC
This one is ok: …url/posts").orderBy("-data")
SELECT * FROM postsByCat WHERE key = {cat} ORDER BY data DESC
This one is ok too: …url/posts").child({cat}).orderBy("-data")
SELECT * FROM postsByCat WHERE key = {cat} AND age =>18 AND age <= 22 ORDER BY data DESC
Well, this one is much more complicated to me at the moment.
I know how to get the most of the data I want but when I have to filter the data in 2 or plus variables the things are much more complicated.
I need a logical explanation on how to do it with NoSQL. I really don’t get how to do that.
That one should be the solution until you realize you must use that with the orderBy directive
So I can’t order it by date Desc AND by startAt & endAt. So THIS is the clue!
How we can go around that?
and you’ve get it. Thanks 
