NoSQL and data persistence?

Question

NoSQL

I read carefully about redis, and am confused.
It looks like I don't understand something, or redis really should be used only as a cache, all sorts of autocomplete and other things like that.
So, we read in the documentation: “Snapshotting is not very durable. „
IS NOT VERY!
With these words, they prioritize those projects where data safety is not important.
How can this be? Preservation is not important or critical only in case of caching or logging something, but they do not position themselves for such projects...
And how can you even allow the loss of even one key in other cases? Let's say snapshotting is done every minute.
Between the action, the user registers on the site, then the server crashes, the user is deleted, is it normal, right
? way to guarantee safety more or less), every second, never.
And it killed me here that they recommend the second method - every second. Very fast and PRETTY SAFE!
However, they note that you can lose data that was added in a second. And they take it just as calmly.
I don't understand.
I ask for help from those who know so that they can show me what I do not understand here, and explain to me whether it is worth switching to NoSQL completely in this situation? I was very interested in this thing, I sit and rejoice, as for the first time in my life I discovered mysql after working with files :))

Answer 1

As the saying goes: "if you like to ride, love to sledge and mess around."
If you need performance anyway, you will be sacrificing reliability.
If on topic, use replication. Using fsunc on every write is kind of silly.
Well, off topic - if the server lies down in the process of writing data to mysql, exactly the same thing will happen to them as when writing to Redis, MongoDB or any other noSql database

Answer 2

Yes, radishes are attractive primarily because of their speed. It's more of an alternative to memcached than a database that you can build your entire application on. When designing one game, we did the following: before the battle, the data from the database was loaded into the radish, during the battle only the radish was used, after the battle we wrote the results back to MySQL.

Answer 3

I thought that radish is such an analogue of memkeshdb?
use mongodb better.

Answer 4

Radishes is a key-value base, is it difficult to build a complex architecture on it? But for the things you said are very good for radishes. I talked with one of the developers of the radish (an add-on for the radish) and he said more than once that the radish as a caching tool is good, but he didn’t advise how the primary storage.

Answer 5

I also wanted to ask a question. And what if locales are stored in the radish (the key is ru.hello_world, the value is 'Hello, world!'). The data is changed at most once a year. How is security here? Is there a chance of losing all (or part)?