When querying large databases with Power BI or Power Query, the design of the query itself sometimes causes long waiting periods because of background loading activities. In order to speed up this process, I’m adding a filter in my tables as one of the first steps, which I can toggle on or off using a central switch. The toggle is a query that will be referenced by an additional line of code:
FilterToggle = if DBFilterToggle=1 then LastQueryStep else FilteredRowStep
Where DBFilterToggle is a query itself with just one value: 0 if I want to have the filter active or 1 if I want to deactivate the filter and see all the data instead.
The cool thing about this method is that the following code will work seamlessly and we can use this toggle in multiple queries at the same time: Just filter your other long tables to your desire and refer them to DBFilterToggle.
This enables me to work with a very few data which will be delivered blazingly fast (due to query folding) and move on with my design very quickly or (often more importantly) during debugging where you need to move through multiple steps quickly in order to find the errors.
I’m not sure, if this is my “invention” or I have seen this before, but so far couldn’t find the source. So please post the source in the comments if you find it.
Enjoy & stay queryious 🙂
When reading horror-stories about Excel-hell describing how dangerous it is to use Excel in corporate environments, I cannot help but to think of this hilarious video describing the fatal consequences of acting without common sense: Just don’t do stupid things with it.
Although Excel comes nearly for free (in relation to what value it delivers) this doesn’t mean that you don’t need to invest in applying proper techniques (like in any other profession). There’s training and best practices for every different need.
But the best thing about Excel seems largely unknown still: Since the invention of Power Query it has never been easier to be save around Excel than before: A magic tool that can solve many of the problems that cause Excel hell: Repetitive tasks: The little adjustments and extensions that pile up when you use your workbook again and again and are often performed without realizing the (meanwhile complex) context of all the standard-Excel-elements involved: Power Query will prevent this mess. It will help you organize and automize your repetitive tasks in Excel.
Excel-reports on SSAS cubes (multidimensional and tabular) can have some flaws that now can be overcome by using Power Query for sourcing your cubedata:
- filter your cube by complete Excel-tables without loading them to the model/cube
- Apply nice number and date formats to non-measure number and date fields in your row- or column section
- create fast detailed reports (multiple attributes in your row sections, overcome the slow MDX that the pivots on cubes produce)
As with the recent Power Query update (26) you can now create your own MDX and DAX-statements for retrieving data from a cube, it is also possible to pass individual parameters from your Excel-sheet to the queries. This is a prerequisite for dynamically reducing the number of returned fields to the query, thereby allowing a decent performance of these reports.
So how about filtering the query by a table that sits in your local Excel file? Can we do an inner-join just like on the SQL-server-source? Read more