1. What is Tableau?
A data visualization tool used to create interactive dashboards and reports.
2. What are the different Tableau products?
Desktop, Prep, Server, Online, Public, Reader.
3. Difference between Live connection and Extract?
- Live: Real-time data, slower.
- Extract: In-memory snapshot, faster.
4. What is a data source filter?
Filter applied at the data-source level before loading to Tableau.
5. What is context filter?
A primary filter that creates a subset of data for other filters. It creates a temporary table .
6. Difference between context filter and normal filter?
Context runs first, normal filters apply on top of context.
7. What is a dimension?
Categorical field (e.g., Name, Date, Region).
8. What is a measure?
Numeric field that can be aggregated.
9. What is the difference between discrete and continuous fields?
- Discrete (blue): Categories.
- Continuous (green): Numeric ranges.
10. What is a parameter?
A dynamic input value that users can change.
11. What is a calculated field?
Custom formula created in Tableau.
12. What is data blending?
Combining data from different sources using a left join (primary + secondary).
13. When do you use data blending?
When joining is not possible (different DBs, different levels of detail).
14. Types of joins in Tableau?
Inner, Left, Right, Full Outer.
15. What is LOD Expression?
Fixed, Include, Exclude — controls granularity of aggregation.
16. Explain FIXED LOD.
Aggregates independently of view-level dimensions.
Example: { FIXED Customer : SUM(Sales) }.
17. Explain INCLUDE LOD.
Adds dimensions to the view for aggregation.
18. Explain EXCLUDE LOD.
Removes dimensions from the view for aggregation.
19. Difference between LOD and Table Calculations?
LOD: Pre-aggregation at source.
Table Calc: Post-aggregation at visualization level.
20. What is a Table Calculation?
A calculation applied on the result set (e.g., Running Total, Rank).
https://www.youtube.com/playlist?list=PLQM-BpTd9ZSumxwKgJjuJjlx2OcP_W516
