What databases are used to store logs?

Question

Database

As far as I understand, simple (technical) logs are stored in some text file. And in what databases are logs stored, for example, transactions, purchases, online users, user / administrator actions, unsuccessful logins, and the like ....

Data that is used not only by developers, but also by managers and administrators.

Answer 1

A very vague question.
For logs, they most often use:

1. ELK
   
2. graylog
   
3. Loki+Grafana
   

Bases:

1. elasticsearch
   
2. clickhouse
   
3. Any other
   

Answer 2

And in what databases are logs stored, for example, transactions, purchases, online users, user / administrator actions, unsuccessful logins, and the like ....

This can be stored in the same database as everything else, but if there is a lot of such data, then you can use some kind of time-series database.
For example, TimeScaleDB or InfluxDB
You can also use Cassanrda for this - it has a very interesting data storage model that can be adjusted for such logs.

Answer 3

Elasticsearch
Clickhouse

Answer 4

Ask for a start what is the format of the logs, you don’t think that these are just strings?
https://messagetemplates.org/
Familiarize yourself with popular practices, problems and approaches, choose the provider log that suits your task / PL. (in general, all structured logs are quite a universal thing, and stuffing it into the same elk should not cause problems)
Logs are not just a data line, they should be informative and convenient for analysis, selections by significant elements, etc.
Then there is the question of their number, shelf life, and the like. Before "where", find out "how" to do it.