Label names?

[rsommer]

Hi,

just a thought about the current label set when using jobs for targeting multiple logical databases in a single server. Currently the target's key is exported as instance label. As of the prometheus docs, instance reflects host:port of the scraped target - which should(?) be the exporter host and it's port and is set by prometheus itself if not present. Wouldn't something like database or dbname be a more suitable label name in this case? The final data in prometheus depends on whether honor_labels is true or false otherwise - so with the same exporter config the final data may differ if instance is used as label. There was a comment regarding labels and upcoming changes in v0.13 - maybe this will be addressed with the next release?

[burningalchemist]

Hey @rsommer, yeah I totally agree. 👍 instance was originally set in the project many years ago, and I also think it's not ideal and a bit misleading. My plan is replace it with target instead with a prior announcement of course. The thing is that the target is not always a database (although, everything technically can be called a database 😆) - we can query json, csv or pgbouncer, for example. That's why to be more target agnostic I want to rename it to target. What do you think?

[rsommer]

Hi @burningalchemist , target would be fine as well - I'm not sure if this should be configurable after all? I think it depends on how people use sql_exporter. If you deploy an instance along every server instance maybe database would be the correct name (because it is highly likely that logical databases are addressed). If someone deploys a single export targeting multiple different hosts with different databases, maybe target is more accurate?

[burningalchemist]

Yeah, fair enough. I wanted to use target everywhere for consistency (between a single target or multiple targets). Let me think about it, we can indeed make it configurable in the end.

[keithf4]

I second the target label for these as well. Matches what's in the job configuration names and avoids confusion with instance.

[burningalchemist]

The PR is created. We set target as a default label (instead of instance) which can be adjusted with --config.target-label= parameter.