Microsoft's recommendations for keeping Power BI Import models lean: get rid of unnecessary rows and columns, aggregate where you can, choose compact data types, do column calculations in Power Query rather than DAX, and switch off auto date/time.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains Data reduction in context, with comparison tables and the common traps.
Terms in this definition
- Power BI
Microsoft's analytics and reporting service. It reaches data held on-premises through the on-premises data gateway.
- Import
A VCF Operations workflow for adopting a vCenter that is already running, whether or not NSX is present, as a workload domain of a VCF 9.0 instance; every one of its clusters is brought in, and NSX gets deployed or joined where needed. Convergence differs by making an existing environment into a management domain instead.
- Get
Key Vault permission on secrets that allows a single secret to be read; App Service Key Vault references need nothing beyond it.
- RID
The relative identifier: the final, unique portion of a SID. Each domain controller issues RIDs from a block allocated to it by the RID master.
- WHERE
Limits a SELECT, UPDATE or DELETE to just the rows meeting a condition. Omit it, and the statement hits every row.
- DAX
Short for Data Analysis Expressions, the formula language you write measures, calculated columns and row-level security rules in, within tabular semantic models in Power BI, Excel Power Pivot or Analysis Services.
- SWITCH
Checks one expression against several candidate values, returning whichever result pairs with the match (or a fallback otherwise). Writing SWITCH ( TRUE (), ... ) avoids nested IF chains: whichever condition is first true wins.
- Auto date/time
With this Power BI Desktop option switched on, each date column in an Import table gets its own concealed date table, unless the column sits on a relationship's many side. That suits basic models, yet it inflates model size and prevents one shared date table from filtering several fact tables.
Related terms
- Live vDisk migration
Relocating the vDisk of a running VM to a different storage container, perhaps to change data reduction or replication factor. A VM under a storage policy cannot do this.
- Overall Efficiency
A Prism capacity figure combining the savings from data reduction, cloning and thin provisioning. Data Reduction Ratio, by comparison, excludes cloning and thin provisioning.