PostgreSQL JSON字段类型与MongoDB

I am building some app where part of it will have pretty much unstructured and changing data which I would like to dump as JSON. As a primary DB I am using PostgreSQL. I have never used JSON field type, but have used MongoDB before. I don't need anything fancy, 99% of the time it will be just storing and getting the data and querying by some fields of the JSON and it is of a scale that one instance of PostgreSQL could handle, nothing epic.I am building some app where part of it will ha