Comparison
Blast radiusvsImpact analysis
Blast radius
you ask how much of the product breaks if this one component dies, and design so the answer is not "all of it".
The scope of impact when a given component fails. Reducing it is the point of cells, shards, bulkheads and per-tenant isolation. It is also the right frame for reviewing a change: not "will this break" but "what breaks with it".
Full entry →Impact analysis
before changing the model you list every dashboard, export and reverse-ETL sync that reads it, and it is longer than you expected.
Working out what will be affected by a change or a failure, by walking lineage downstream. It is what makes a schema change a planned event rather than a surprise, and it is the first thing done in a data incident because the population affected determines who to tell. Its quality is bounded by how far lineage extends: it usually stops at the warehouse boundary, and the spreadsheet somebody built on an export is invisible.
Full entry →