One of the interesting features of NoSQL databases is their schema-less mode of operation. This feature is very useful during project prototyping and early development since at early the stages of development of projects all data structures are not clear or have been defined yet. The reason of this post is not to discuss about that subject, but to show that sometimes you can also use NoSQL with a more traditional database engine like PostgreSQL.

Since version 9.3 there is support for JSON however with version 9.4 there is even better support with the new type JSONB. I will now show how to use the basic JSON type in a simple REST application written with Vert.x3:

Now all you need to do is play with this REST service, for this you can use curl to create a sale:

$ curl \
    -i \
    -H "Content-Type: application/json" \
    -X POST \
    -d '{"id": 1, "customer_name": "John", "items": {"description": "milk", "quantity": 4}}' \
    http://localhost:8080/sales
 
HTTP/1.1 201 Created
Content-Length: 0

And if you want to read that new document:

$ curl -i -H "Accept: application/json" -X GET http://localhost:8080/sales/1
HTTP/1.1 200 OK
content-type: application/json
Content-Length: 75
 
{"id":1,"customer_name":"John","items":{"description":"milk","quantity":4}}