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by miki123211 1985 days ago
I use the same system (a JSON file protected with a mutex) for an internal tool I wrote, and it works great. For us, file size or request count is not a concern, it's serving a couple (internal) users per minute at peak loads, the JSON is about 150 kb after half a year, and old data could easily be deleted/archived if need be.

This tool needs to insert data in the middle of (pretty short) lists, using a pretty complicated algorithm to calculate the position to insert at. If I had used an RDBMS, I'd probably have to implement fractional indexes, or at least change the IDs of all the entries following the newly inserted one, and that would be a lot of code to write. This way, I just copy part of the old slice, insert the new item, copy the other part (which are very easy operations in Go), and then write the whole thing out to JSON.

I kept it simple, stupid, and I'm very happy I went with that decision. Sometimes you don't need a database after all.
2 comments
Quekid5 1985 days ago
As long as you're guaranteeing correctness[0], it's hard to disagree with the "simple" approach. As long as you don't over-promise or under-deliver, there's no problem, AFAICS.

[0] Via mutex in your case. Have you thought about durability, though. That one's actually weirdly difficult to guarantee...

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a1369209993 1985 days ago
> Have you thought about durability, though. That one's actually weirdly difficult to guarantee...

Strictly speaking, it's literally impossible to guarantee[0], so it's more a question of what kinds and degrees of problems are in- versus out-of-scope for being able to recover from.

0: What happens if I smash your hard drive with a hammer? Oh, you have multiple hard drives? That's fine, I have multiple hammers.

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winrid 1985 days ago
What happened to the first hammer :D
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Quekid5 1983 days ago
I guess it wasn't Durable.
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AlfeG 1985 days ago
That's good. But single file could break on powerloss. I use sqllite. It's quite easy to use, not a single line though.
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masklinn 1985 days ago
Their point about schema migration is completely true though. An SQLite db is extremely stateful, and querying that state in order to apply schema migrations (for both the data schema and the indexes) is bothersome.
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