A rename upstream, and eleven dashboards
The application team renamed a column in a migration. It was a correct, reviewed change. Eleven dashboards broke that afternoon, and two more produce numbers that are wrong without producing an error.
What you would do first
Answer before revealing anything. The value of the exercise is entirely in committing to a diagnosis you can be wrong about.
- 1Establish which models actually failed and which produced a wrong number silently. The silent ones are the finding.
- 2Trace one broken dashboard upstream and count how many models pass the column through unchanged.
- 3Ask whether the producing team had any way of knowing this column was consumed. Usually they did not.
- 4Check whether the two silently wrong dashboards were reading a column that still exists but now holds something else.
What is actually going on
The trap
The fix that looks right. Read it even if you got the answer — especially then.
Ask the application team to revert the rename. It restores the dashboards in an afternoon and establishes that the platform's hidden coupling is the producing team's problem — so the next migration is either blocked or shipped without telling you, and both outcomes are worse than the original break.