Store in memory or in local database

Question

I'm developing an app in which I'll need to collect, from a MySQL server, a 5 years daily data (so, approximately 1825 rows of a table with about 6, 7 columns).

So, for handling this data, I can, after retrieving it, store it in a local SQLite database, or just keep it in memory.

I admit that, so far, the only advantage I could find for storing it in a local database, instead of just using what's already loaded, would be to have the data accessible in a next time the user were to open the app.

But I think I might not be taking into account all important factors.

Which factors should I take into account to decide between storing data in a local database or keep it in memory?

Best regards, Nicolas Reichert

Answer 1

With respect, you're overthinking this. You're talking about a small amount of data: 2K rows is nothing for a MySQL server.

Therefore, I suggest you keep your app simple. When you need those rows in your app fetch them from MySQL. If you run the app again tomorrow, run the query again and fetch them again.

Are the rows the result of some complex query? To keep things simple you might consider creating a VIEW from the query. On the other hand, you can just as easily keep the query in your app.

Are the rows the result of a time-consuming query? In that case you could create a table in MySQL to hold your historical data. That way you'd only have to do the time-consuming query on your newer data.

At any rate, adding some alternative storage tech to your app (be it RAM or be it a local sqlite instance) isn't worth the trouble IMHO. Keep It Simple™.

If you're going to store the data locally, you have to figure out how to make it persistent. sqlite does that. It's not clear to me how RAM would do that unless you dump it to the file system.