Web Development Architecture (FOCUS: Database/CouchDB) - web-services

Question

I had few questions that might be easy for others, but that I couldn't wrap my head around.
In developing a "PRODUCTION LEVEL" full-stack web application(node.js/react/webpack),
1) Where do you set up your database? (when developing, I'm using apache couchdb running on my localhost, but when deployed, is cloud database(cloudant) the only solution? or am i missing something?)
2) Is it recommended to deploy my server(node.js) to either digital ocean/aws/heroku, AND set up a third party database else where? (in my case, I'm have to use either Digital Ocean/Aliyun(Chinese Web Service), but they don't seem to have a database package that comes with couchDB) - What is the practical solution for production level application?
3) If cloud database is the practical solution, What Do I do if there is no database storage center for CouchDB located in China? is there a cloud database storage that universally saves all noSQL data regardless of your type of DB? (mongoDB, couchDB, etc.,)
4) AWS/Heroku provides add-ons where you can connect cloud database to my application, does this make the speed of my application faster? For Digital Ocean, it shows article about setting up CouchDB with their service, but does that mean that database will be available for my users to access? or is that just for development purposes
5) Where and How does "Docker" come in to play to help in my situation?
Sincerely,

Answer 1

I cannot say for CouchDB, but I have hosted multiple web applications on AWS using their RDS Database (MySQL). The service you choose (AWS/DO/Heroku), depends on your application and your requirements (pricing etc).
I don't think AWS has a package for MongoDB, but there is a third party service MongoLabs, which can host the MongoDB Database, I bet there would be some out there for CouchDB too.
Or if you cannot get a third party hosting, consider installing the database on your server itself. Getting a VPS from either DO or AWS and setting it up yourself could be an option in that case. The link you mentioned in your last paragraph would help you here. And yes, if you use that and let node connect to it, you can use it just like any other cloud based database, just that it would be on your server.
I haven't used Docker, so cannot say if and how that could help
UPDATE: (reply to comment)
A VPS is a server in the cloud. You don't set up the database on your local computer, no one can access that. You set up your database on the VPS (in the cloud) and then everyone can access that.
A VPS is like your own clean copy of server (ubuntu/fedora) in the cloud, so you can pretty much do anything on it, like your local computer. So basically your database would also be in the cloud.
There are actually 2 ways you could do that.
Get a VPS, install your database and set up your node.js server on the same VPS. Your node application would access the database on the same VPS.
Get a VPS specially for the database, and set up your node.js on another VPS, this would separate the database and node app on two different servers.

Answer 2

To answer part of your question... if you set up a CouchDB server on Digital Ocean (or on AWS, Azure, Google Cloud etc) it will be available to your production users, not just you. You will want to set up security/firewall to limit who can access your server of course.
Cloudant provide CouchDb as a service, in other words you would not have to install the software or manage a server.
With Digital Ocean/AWS/Azure/Google it is down to you to manage the virtual server and the database/other software on it. You can install CouchDb on any of these services and you can install both NodeJS and CouchDb on the same virtual server if you wish.
Bitnami have a CouchDb package that you can use to deploy CouchDb on to several of the major hosting companies, which makes the setup process easier.
I see that AWS and Azure have data centres in China, but at the moment Digital Ocean do not as far as I am aware. I hope this helps