DISTINCTCOUNT on a text column of a fact table
"DISTINCTCOUNT on a text column of a fact table" is one of the performance checks Auditabi runs on a Power BI semantic model. n measure(s) count distinct values of a text column on a fact table. It is a low-severity finding: hygiene and maintainability, worth fixing when you next touch the object. Count the surrogate key instead, or move the attribute to a dimension and count the dimension rows.
What is detected
n measure(s) count distinct values of a text column on a fact table. The engine builds a dictionary of every distinct string at query time, which is the slowest form of the operation.
Why it matters
Hygiene and maintainability. Fix when touching the object.
How to fix it
Count the surrogate key instead, or move the attribute to a dimension and count the dimension rows.
Does your model fail this check?
Free static audit with the exact objects, no account, nothing stored.
More DAX checks
- Arithmetic or comparison on a measure that returns text
- Measure returning text in one branch and a number in another
- Share denominator clears a fact-table column instead of the dimension
- "Previous period" window overlaps the current one
- Percentage label built without ×100
- Percentages and amounts summed together