About current vs last for some panels

Hi,
I was running grafana 7.3.6 and recently upgraded to 9.0.5; The datasource of my grafana is prometheus

well, the settings of alerts changed completely, I am still trying to figure out the changes that I need to make to my alerts becase I am getting a ton of useless info in my alerts (email and telegram) and I am finding this not very intuitive. before you could define a threshold and you would see the red line with the little heart, … and this idea changed completely. if anyone can provide a guide on how to understand the new alerts and maybe migrate, I would appreciate

my main point for this thread:
In legend, I used to see the current value, so if I was getting nothing I would customize it to character -

In this version, I dont see current anymore, Now we have last and last*; so if I use either of them, I would get the last value but the problem is that last does not show - for no value, so it would show the last non-null value, basically the same as for last*,

in other words, no matter if I use last or last*, even when there is no value, it would still show the last value

can anyone explain whats going on?

ps: if I change in the query from range to instant, it would show the current value, but the graph would disappear. I admit that I am very confused with most of these changes

thanks

The alerting platform that was behind 7.3.6 is completely deprecated, and the new alerting platform is just that–entirely new. This blog post might help sort things out: