8. Adding Columns: Power Query Add Column Tab and DAX Calculated Columns
8.1 The Add Column Tab at a Glance
Open the Power Query Editor (Home › Transform data) and click the Add Column tab. Everything here creates a new column and keeps the original (unlike the Transform tab, Module 6.3).
| Group | Commands |
|---|---|
| General | Column From Examples, Custom Column, Invoke Custom Function, Conditional Column, Index Column, Duplicate Column |
| From Text | Format, Merge Columns, Extract, Parse |
| From Number | Statistics, Standard, Scientific, Trigonometry, Rounding, Information |
| From Date & Time | Date, Time, Duration |
| AI Insights | Text Analytics, Vision, Azure Machine Learning (need Premium/Fabric capacity; not covered here) |
Power Query column or DAX column?
A good rule: create columns as far upstream as possible, in the source database, then Power Query, and only then DAX. Power Query columns are compressed better and keep the model simpler. Use a DAX calculated column fakt when you need model features such as RELATED across relationships (संबंध) or values that depend on other tables in the model (8.11).
Ravindra Bagale's Tip
Mitrano, khup students add the same column in Power Query and as a DAX calculated column, and later forget which one the report uses. Decide once: static row-level columns go in Power Query. Delete the duplicate so only one version exists. Dhyan rakho!