Speed up a slow Power BI or Tableau dashboard
Diagnoses why a BI report loads slowly and gives a ranked list of fixes across data model, queries, calculations, and visuals.
The prompt
Help me speed up a slow BI dashboard.
Tool: [Power BI / Tableau / Looker / other]
Connection mode: [import/extract, DirectQuery/live, mixed]
Symptoms: [e.g. "page takes 25 seconds to load", "slicers lag", "refresh times out"]
Data model: [tables, row counts, relationships, cardinality of key columns]
Heavy calculations: [PASTE slow DAX measures, calculated fields, or LOD expressions]
Page design: [number of visuals per page, filters, custom visuals]
Performance diagnostics: [PASTE Performance Analyzer, Performance Recorder, or query log output if available]
Diagnose across these layers:
1. Data model: unnecessary columns, high-cardinality columns (timestamps, IDs, long text), wide flat tables vs. a star schema, bidirectional or many-to-many relationships, calculated columns that should be done upstream.
2. Source and queries: DirectQuery hitting slow views, missing aggregations, unpushed filters, no incremental refresh.
3. Calculations: iterator functions over large tables, repeated sub-expressions (use variables), complex row-level logic, nested LODs or table calculations.
4. Visuals: too many visuals per page, high-cardinality tables, heavy custom visuals, many slicers cross-filtering each other.
5. Filters: context filters vs. regular filters, filters on calculated fields.
Return:
- The likely bottlenecks, ranked by impact, with the evidence from what I shared.
- A fix list: Change | Layer | Expected impact | Effort | Risk.
- Rewritten versions of any slow calculations I pasted.
- How to measure before and after so I can prove the improvement.
Highlighted [brackets] are blanks to replace with your own details.
Fill in the blanks and use this promptMore Data & Analysis prompts
What to fill in
- Power BI / Tableau / Looker / other
- import/extract, DirectQuery/live, mixed
- tables, row counts, relationships, cardinality of key columns
- number of visuals per page, filters, custom visuals
How this prompt is built
This prompt follows the RTF structure (Role, Task, Format). RTF tells the model who to be, what to do and what shape the answer should take. It is the quickest structure that still gives noticeably better results than a bare request.
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