The scenario is that there’s a source system, and there’s a table in a warehouse that is being used to report on it. Maybe it’s being populated by Integration Services or Data Factory. Maybe it’s being populated by T-SQL. I don’t really care. What I care about is whether the data in the warehouse is a true representation of what’s in the source system.
If it’s not a true representation, then we have all kinds of problems.
Mostly, that our warehouse is rubbish.
Read on for an example of how this might occur and what you can do to prevent it.