Performance comparision: PHP&Json&Database - PHP&Json&Text File - PHP&Json&Parsing

I have a general question about what is faster between different options.

I have a site that works like this.

When the user fill the form, a PHP file (included) receive the selected option and parse multiple json file resident on another server.

The problem is that this operation is quite slow (there will be a part with database and cronjobs for automated updates and so obtain fast query) so I was wandering what may it be the fast way to retrive data and show on page.

The option I thought are: 1) PHP - JSON - NORMAL PARSE (the way I've used right now); 2) PHP - JSON - DATABASE (save everything on database and make multiple query); 3) PHP - JSON - TEXT (save every file I recover in a txt file so I have a rapid access to data?).

If you need I can be much more specific but maybe the answer is so simple that you don't need to read 200 rows of explanations.

Thx.

Alberto

via Chebli Mohamed