Data Cleaning Exercises

Reference · Visual workspace

Flag rows in Visual workspace

Add a true/false column that marks rows matching a condition, keeping every row.

When to use it

Unusual but possibly legitimate values that need human review.

How

Add step → Rows → Flag rows. Name the new column and set the condition.

Flag needs_review where amount > "5000.00"
  • Comparisons with a missing value are false.

Pitfalls

  • Deleting or capping instead of flagging.
  • Getting the boundary wrong (> versus >=).

Lesson: Flag outliers, don't delete them

Practise it: Flag large transactions, keep refunds