[prometheus-postgres-exporter] Remove pg_database query

[ahmadsherif]

After the merge of prometheus-community/postgres_exporter#613, postgres-exporter installed by recent versions of the prometheus-postgres-exporter Helm chart is throwing 500 errors like:

HTTP/1.1 500 Internal Server Error
Content-Type: text/plain; charset=utf-8
X-Content-Type-Options: nosniff
Date: Tue, 29 Nov 2022 11:08:41 GMT
Content-Length: 1418

An error has occurred while serving metrics:

4 error(s) occurred:
* collected metric "pg_database_size_bytes" { label:<name:"datname" value:"template0" > label:<name:"server" value:"10.188.0.2:5432" > gauge:<value:8.225283e+06 > } was collected before with the same name and label values
* collected metric "pg_database_size_bytes" { label:<name:"datname" value:"postgres" > label:<name:"server" value:"10.188.0.2:5432" > gauge:<value:8.373103e+06 > } was collected before with the same name and label values
* collected metric "pg_database_size_bytes" { label:<name:"datname" value:"template1" > label:<name:"server" value:"10.188.0.2:5432" > gauge:<value:8.373103e+06 > } was collected before with the same name and label values
* collected metric "pg_database_size_bytes" { label:<name:"datname" value:"default" > label:<name:"server" value:"10.188.0.2:5432" > gauge:<value:8.373103e+06 > } was collected before with the same name and label values

So we're removing the YAML query to avoid such conflict.

Signed-off-by: Ahmad Sherif [email protected]

What this PR does / why we need it

Which issue this PR fixes

(optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged)

• fixes #

Special notes for your reviewer

Checklist

• DCO signed
• Chart Version bumped
• Title of the PR starts with chart name (e.g. [prometheus-couchdb-exporter])

[monotek]

as this removes a currently used config this would be considered a breaking change.

[monotek]

Please also update readme upgrading section and describe the change there.

[moolitayer]

@monotek Is this really a breaking change, cosidering we get the same metric from a built-in collector?
Should this be considered a patch?

[monotek]

@monotek Is this really a breaking change, cosidering we get the same metric from a built-in collector? Should this be considered a patch?

Yes, as we change a default value of the chart.
Somebody might have adjusted the query slightly and would need the info of this change, so he can remove it manually.

[sergelogvinov]

Hello, i've got the same error, and almost did the same PR.
The postgres_explorer adds this metrics in the core https://github.com/prometheus-community/postgres_exporter/releases/tag/v0.11.0

So, braking changes was after upgrade version to 0.11.0
Currently, the default values of the cart do not work. In my opinion, this PR is hot-fix.

So, do you have a plan then it will be merged?
Thank you.

[moolitayer]

@monotek friendly ping

[moolitayer]

@ahmadsherif @monotek thanks for the fix!