Most of us design a "CRUD" (Create, Read, Update and Delete) matrix for an application's database. And if you are really thorough, you create a data dictionary that shows what data goes where and why.
The problem with these documents is that over time more data elements are added (sometimes a lot of them at once) and data meanings change, and the documentation isn't kept up to date. Add to that the fact that most organizations store redundant information in different platforms and formats, and it becomes nearly impossible to create a comprehensive data map. And this is only the structured data - add in Word documents, and the worlds largest database platform (Excel) and you're really talking about the wild west.
But this is the same situation that computers helped solve to begin with - data on paper was spread all over the organization and there was no easy way to combine or reference it all. Now we just expect that the car dealership in Iowa can look up our warranty on a car we bought in Florida. So we took an impossible task and fixed it with technology.
So should there be an effort to map a company's data entirely? Or is it even possible...