Restricted to visual calculations, EXPAND works out a value one step down the visual's hierarchy, for example the mean across child rows. EXPANDALL instead goes straight to the bottom, leaf level.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains EXPAND in context, with comparison tables and the common traps.
Terms in this definition
- Hierarchy
Lets report users drill up and down through totals by stacking a dimension's levels in order, for example region, then city, then address, in a semantic model.
Related terms
- AI splits
A decomposition tree mode, shown by a light-bulb icon, in which Power BI itself picks the field to expand next, looking for high or low values in absolute or relative terms. It is unavailable in Power BI Report Server, Azure Analysis Services and publish-to-web reports.
- AuditData
When audit search results are exported to CSV, this field carries the full detail of every record as JSON. Excel's Power Query can expand that JSON into individual columns.
- Incident graph
Part of the attack story on an incident in Defender: a diagram linking its alerts and entities, which you can expand with blast radius analysis.
- Investigation graph
Draws the entities in a Sentinel incident and lets you expand each one through exploration queries. It only works if entities are mapped and the incident is 30 days old or less.
- NOEXPAND
Tells the optimiser to read an indexed view through its own index rather than substituting the view's definition. Standard edition requires this hint, while OPTION (EXPAND VIEWS) works the other way round.
- Table.NestedJoin
Merge queries relies on this M function, which matches rows across two tables by their keys and nests the matches in a new column you can expand. Supported join kinds cover inner, outer, anti and semi joins, though the Merge dialog omits the LeftSemi and RightSemi options.