1. What are Dimensions and Measures?
Dimensions are categorical fields (Region, Customer).
Measures are numeric fields (Sales, Profit).
2. What is the difference between Discrete and Continuous fields?
Discrete creates headers (Blue).
Continuous creates axes (Green).
3. What is a Tableau Extract?
A compressed snapshot of data stored in Tableau for faster performance.
4. What is the difference between Live Connection and Extract?
- Live: Queries database in real time.
- Extract: Uses stored snapshot data.
5. What is a Hierarchy?
A drill-down structure such as:
Region → State → City
6. What is a Set?
A custom subset of data members.
Example:
Top 10 Customers
Top 5 Products
7. What is a Group?
Combines multiple dimension members into a single category.
Example:
Karnataka + Tamil Nadu = South India
8. What are Calculated Fields?
Custom fields created using formulas.
Example:
SUM([Sales]) - SUM([Cost])
9. What is an LOD Expression?
Calculates values independent of the visualization level.
Example:
{ FIXED [Customer ID] : SUM([Sales]) }
10. What are the types of LODs?
- FIXED
- INCLUDE
- EXCLUDE
Example:
{ FIXED [Region] : SUM([Sales]) }
11. What is a Context Filter?
A primary filter applied before other filters.
Used to improve dashboard performance.
12. Difference between Table Calculation and LOD?
| LOD | Table Calculation |
|---|---|
| Calculated before visualization | Calculated after visualization |
| Uses source data | Uses displayed data |
Example:
{ FIXED [Customer] : SUM([Sales]) }
vs
RUNNING_SUM(SUM([Sales]))
13. What is Data Blending?
Combining data from multiple sources based on common fields.
Example:
Sales Data + Target Data
14. Difference between Join and Blend?
Join
- Happens before aggregation.
- Same data source layer.
Blend
- Happens after aggregation.
- Different data sources.
15. What are Relationships in Tableau?
Logical connections between tables introduced in Tableau 2020.2.
They preserve each table's granularity.
16. What is Row-Level Security (RLS)?
Restricts data visibility by user.
Example:
USERNAME() = [User]
Users see only authorized data.
17. What is Tableau Order of Operations?
- Extract Filter
- Data Source Filter
- Context Filter
- Dimension Filter
- Measure Filter
- Table Calculation Filter
Frequently asked in interviews.
18. How do you improve Tableau Dashboard Performance?
- Use Extracts
- Reduce Quick Filters
- Use Context Filters
- Avoid heavy LODs
- Optimize joins
- Reduce marks
19. What are Parameters?
User-defined dynamic inputs.
Example:
Top N Customers
Sales Threshold
Parameter Example:
IF SUM([Sales]) > [Threshold]
THEN "High"
END
20. Difference between INCLUDE, EXCLUDE and FIXED?
FIXED
Ignores view level.
{ FIXED [Region] : SUM([Sales]) }
INCLUDE
Adds dimensions to the calculation.
{ INCLUDE [Customer] : SUM([Sales]) }
EXCLUDE
Removes dimensions from the calculation.
{ EXCLUDE [Customer] : SUM([Sales]) }
Most Important Interview Topics (Asked Very Frequently)
- LOD Expressions (FIXED, INCLUDE, EXCLUDE)
- Joins vs Relationships vs Blending
- Context Filters
- Order of Operations
- Row-Level Security (RLS)
- Dashboard Performance Tuning
- Table Calculations
- Parameters
- Sets
- Extract vs Live Connection
These 10 topics alone cover a large share of Tableau interview questions for 3–10+ years of experience.
