# Aggregating dimensions with ATTR, MIN, MAX and COUNTD

*Tableau Consultant Study Guide · Design and Troubleshoot Calculations and Workbooks · Last updated November 3, 2026 · https://www.certifyforce.com/study-guide/tableau-consultant/design-and-troubleshoot-calculations-and-workbooks/aggregating-dimensions-with-attr-min-max-and-countd*

Choose how to aggregate a dimension (Attribute, Minimum, Maximum, Count, Count (Distinct)) from what each mark must show, use ATTR to keep a dimension as a label without partitioning a table calculation, and apply the rules for aggregate calculations, default aggregations and the Dimension aggregation on measures.

- Certification: Salesforce Tableau Consultant
- Exam section: Design and Troubleshoot Calculations and Workbooks
- Study guide: https://www.certifyforce.com/study-guide/tableau-consultant

**Official exam objective:**

> Implement aggregations that include dimensions.

## What the exam expects

- Pick the aggregation for a dimension (Attribute, Minimum, Maximum, Count or Count (Distinct)) from what each mark must return.
- Explain how ATTR is computed and what its asterisk means.
- Use ATTR so a dimension labels a view without partitioning a table calculation.
- Apply the rules for aggregate calculations: no mixing aggregated and disaggregated values, AGG fields, and where a default aggregation can and cannot be set.
- Use the Dimension aggregation or disaggregation when a measure's individual values must become marks.

Key terms:
- **Aggregating a dimension:** applying Minimum, Maximum, Count or Count (Distinct) to a dimension, which creates a temporary measure column.
- **ATTR (Attribute):** returns the value when all rows in the group share it, otherwise an asterisk.
- **Aggregate calculation:** a calculation built from aggregated fields; on a shelf it shows as AGG(...) and cannot be aggregated further.
- **Default aggregation:** the aggregation Tableau applies automatically when a measure is dragged to a view.

## Key facts

| Fact | Detail | Source |
|---|---|---|
| Dimension aggregations | Minimum, Maximum, Count, Count (Distinct), plus Attribute | [Data Aggregation in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_aggregation.htm) |
| ATTR formula | IF MIN = MAX THEN MIN ELSE "*", computed after the initial query | [Data Aggregation in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_aggregation.htm) |
| ATTR and nulls | Null values are ignored | [Data Aggregation in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_aggregation.htm) |
| COUNT vs COUNTD | Number of items vs number of distinct items; nulls not counted | [Aggregate Functions in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_calculatedfields_aggregate_create.htm) |
| "Requires extract" | COUNTD on pre-8.2 Excel or Text workbooks, legacy connections, Access | [Data Aggregation in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_aggregation.htm) |
| MAX on a date | Most recent date; as an aggregation, no date hierarchy | [Aggregate Functions in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_calculatedfields_aggregate_create.htm) |
| SUM | Numeric fields only | [Aggregate Functions in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_calculatedfields_aggregate_create.htm) |
| Default aggregation | Not for calculated fields that already contain an aggregation | [Data Aggregation in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_aggregation.htm) |
| Published data sources | Default aggregation is set at first publish | [Data Aggregation in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_aggregation.htm) |
| INCLUDE and EXCLUDE results | Always measures | [Overview: Level of Detail Expressions](https://help.tableau.com/current/pro/desktop/en-us/calculations_calculatedfields_lod_overview.htm) |

## Check yourself

- When can MIN on a string field from a database return a value that is not first in plain alphabetical order?
- When does Count (Distinct) show "Requires extract"?
- What happens to the date hierarchy when MAX is used as an aggregation on a date field?
- Why is MAX(SUM(Sales), Profit) rejected while MAX(SUM(Sales), SUM(Profit)) is accepted?

## Sources

- [Data Aggregation in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_aggregation.htm)
- [Aggregate Functions in Tableau](https://help.tableau.com/current/pro/desktop/en-us/calculations_calculatedfields_aggregate_create.htm)
- [Overview: Level of Detail Expressions](https://help.tableau.com/current/pro/desktop/en-us/calculations_calculatedfields_lod_overview.htm)
- [INCLUDE Level of Detail Expressions](https://help.tableau.com/current/pro/desktop/en-us/calculations_calculatedfields_lod_include.htm)
- [EXCLUDE Level of Detail Expressions](https://help.tableau.com/current/pro/desktop/en-us/calculations_calculatedfields_lod_exclude.htm)

## About the full unit

The "Core concepts", "Exam traps" and "Worked scenario" sections of this unit, its 7 linked practice questions, and unlimited timed mock exams are included with the Tableau Consultant pack (USD $19): https://www.certifyforce.com/practice-exams