Let's assume that Stackoverflow offers web services where you can retrieve all the questions asked by a specific user. A request to get all question from user A can result in the following json output:

{
    {
        "question": "What is rest?",
        "date_created": "20/02/2010",
        "votes": 1,
    },
    {
        "question": "Which database to use for ...",
        "date_created": "20/07/2009",
        "votes": 5,
    },
}

If I want to manipulate and present the data in any ways that I want, will it be wise to dump it in a local database? At some point, I will also want to retrieve all answers for each question and store them in a local database.

The workflow that I'm thinking is:

1. User logs in.
2. Web services retrieve all questions asked by the logged in user, dump them in a local database.
3. User wants all answers for a specific question, another web service does the retrieval and dump them in a local database.
4. After user logs out, delete from the local database all questions and answers from that user.