# Dropbox datastore

Dropbox seems to have a feature where it can be used as a database.

This would be really cool to use for memoized functions, that can be restored on several computers and sessions.

I have a function that is hard to compute, but the output is always just a natural number, and I wish to make Mathematica remember all computed values, between sessions and both at home and at work.

Has anyone tried this solution? What other options are there?

I think that a database or something similar is a must; a plain-text file in a Dropbox folder can be corrupted if the program crashes during writing, and it is tricky to know when to update the file.

• If you have V10 then Dropbox is supported out the box, so it shouldn't be too hard. But the Wolfram Cloud, i.e. CloudPut, is a more natural option I think. – C. E. Sep 29 '14 at 17:48
• Of course it has it built-in, haha. Too bad my office only have V9. But the dropbox API is different from the Mathematica functions, which only work with files... – Per Alexandersson Sep 29 '14 at 17:56
• Come to think of it, you can probably use Pastebin as I did here. Their API lets you do the three basic things you might want to do: create a new data file, delete a data file and list all data files. (It's not the optimal database solution of course, but besides that...) – C. E. Sep 29 '14 at 22:14
• @PerAlexandersson, can you give details on your corruption worries and "when to update"? Have you had issues using Import/Export? We use Dropbox and Google apps, like Gsheets for online coediting, with Mathematica with no problems. Dataset size on the order of 250m LeafCount. – alancalvitti Sep 30 '14 at 14:18
• I was more thinking along the line of memoization, but storing computed things in the database also. Thing is, if I run a batch for computing a large set of polynomials, say, and the kernel crashes, all partial results are lost. If I append to a raw file, the file handler is still open, so there might be data loss. Besides, I think import/export on EVERY new result computed, is a bit tough on the hard-drive (and also slows down the computation immensely), although I suppose writing to a remote location is even slower... – Per Alexandersson Sep 30 '14 at 19:14