Agenda:
1. Introduction- Understanding the importance of having a high-performant solution
- Where do I start? How to identify the poorly performing area(s)
- Why is data modeling so important?
- Star-schema vs flat table
- Costs of not having a star-schema in place
- Role-playing dimensions
- Bi-directional filters
- Understanding the core components of the VertiPaq engine
- Describing different data compression encoding types
- Understanding the concept of cardinality levels
- Describing Auto Date/Time and calculated columns caveats
- Demo: Reducing Data model size applying various techniques (splitting columns, changing data types, reducing the cardinality levels, etc.)
- Understanding the concept of aggregations in Power BI
- User-defined vs Automatic aggregations
- Demo: Create user-defined aggregations, make Power BI “aware” of it, and unleash the full power using the Composite model; Check if the aggregations are being used by Power BI
- Introduction to the data transformation process
- Best practices for transforming the data
- Using Power Query Editor for data transformation
- Understanding the concept of Query folding
- Describing the most common scenarios for breaking Query folding
- Visualizing data refresh process
- Demo: understand the importance of Query folding by showing the difference in performance between the queries that return exactly the same results: one with query folding, one without
- Introduction to DAX calculations as part of enriching semantic model
- Understanding how little nuances in the DAX query can produce a significant difference in the performance
- Describing most common mistakes when writing DAX calculations
- Understanding what affects the report rendering time
- Using Performance Analyzer feature to identify the slowest report elements
- Best practices for visuals rendering time
- Demo: redesign Power BI report page to perform 5x faster, without violating the original report design
- Understand the difference between Import and DirectQuery mode
- Understand use-case scenarios for DirectQuery mode
- Best practices for using DirectQuery mode
- Things to avoid when using DirectQuery mode
My name is Nikola Ilić and I make music from the data. I’m really passionate about everything related to data. I have multi-year experience working with various flavors of data, predominantly with Microsoft’s BI stack. Therefore, I will write in most cases about SQL Server, T-SQL, SSAS, SSIS, SSRS, Power BI, Azure, etc. But, since I’m really curious by nature and always trying to learn something new, I will also consider writing about other data-related tools and techniques.
