How to tell if a project needs a NoSQL database solution? How to tell if a project needs a NoSQL database solution?

I think that SQL limits define it. If the project needs bigger database or bigger fields then it needs NoSQL. 

Am I right?

I looked into NoSQL database limits. They are below:

For an example I'm using MongoDB assuming that DynamoDB has similar numbers. 

Mongo can be installed on a number of computers/nodes. PostgreSQL does not provide built-in tool for sharding, however citus is around.

MongoDB supports databases up to 64 terabytes and document size is 16 megabytes.  

MySQL has a database limit of 256 terabytes, 64TB the maximum size for a table and record limit of 4 gigabytes.

PostgreSQL has no limit on database (4 terabytes does exist somewhere for testing) and it has a limit of 1 gigabytes for the size of any one field in a table and again 64TB the maximum size for a table.

Is there anything else that is relevant for decision making process?
How to tell if a project needs NoSQL database solution?
  
  I think that SQL limits define it, if project needs bigger database or bigger fields than it needs NoSQL.
  
  Am I right?


You are not right ;)

Choosing NoSQL over a relational database has a lot more to do with business reasons like:


do we have people on the team already familiar with NoSQL database?
will it be cheaper (in terms of hardware, licensing, support, etc)?
will it be faster (because of tooling, or the schema-less nature of document databases, etc)?


It also has a lot to do with the types of data you're storing, and your data modeling requirements.  For instance, if your application needs to store large amounts of XML or JSON data, or if every entity you save might be slightly different, you might be better off with NoSQL. But if you need to model relationships and enforce constraints, referential integrity, etc, then you would likely be better off with a relational DB.