Hi there,
I import 20k rows every hour in DB. Then I show graph in Grafana (one column is varchar and there is a key name is nodename). But it is very slow. At this moment I use MySQL.
Which type od datasources would be the besst (the fastest)?
It depends on your data structure/queries/requirements/budget/… Make a POC and stress test for your case and you will see. My general recommendation: InfluxDB.