Drilling Down
"Drilling Down" is a business intelligence term used to describe looking at data is smaller units.
For example you might want to a look at the total sales for all widgets, then all widgets in England, then all widgets in England that are blue.
This traditional use of this term is doesn't sit well with the way that PerBI works, equivalent functionality is achieved in a completely different way by using
Data Manipulation Commands .
This is because traditional BI requires you decide on what you want to view when creating the model, not when you are looking at the data.
Temporarily Delete Rows.
PerBI use Drop and Keep for filtering data as it sometimes easier to ignore values rather than specify the interesting ones.
The core concept of PerBI is that you can filter, temporarily delete, rows of data using very complex filters and you can have different charts using different filters.
You can also create multiple charts that use the same filter, so changing the filter in one chart automatically updates any other charts using that subset.
This is different to the traditional business intelligence product that precalculates a set of results and you can only filter based on the decisions made at the precalculate stage.
The advantage of doing this precalculation is that you can represent more data using less memory, PerBI couldn't work with say the day's transactions for Amazon or all the journeys made using Uber yesterday.
But if you have a smaller amount of data for many people it may be much easier to manipulate the data using PerBI.
Data Manipulation Commands
Data Manipulation Commands are simply four items in a dialog box that allow you to temporarily remove rows of data from your model.
Looking at the example opposite we are excluding any rows where the
vehicle is more less than or equal to
10 years old. These simple actions can be built up into quite complex filters.
Advanced Scripting Language
For real power users, the Advanced Scripting Language allows complex logic to be used in deciding which rows to drop or creating entirely new data.
Initially this looks intimidating, but once you get used to it you really start to get the point of the product.
Dialog boxes and menus are always restrictive, they only allow what the dialog creator thought would be required.
This little bit of ASL drops rows where the cover is comprehensive, the vol xs is over £250 and the main driver has less than three years experience. Not something that it easy to cover with a generic dialog selection box.