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Transform Tab – Power Query

? Transform Tab – Power Query

✨ Quick Overview

The Transform Tab is for modifying data within your existing columns. Unlike the "Add Column" tab, it cleans the data "in-place," keeping your table lean and efficient.

? Key Concepts

  • Overwrites current column data
  • Keeps column count the same
  • Every action creates an Applied Step

? Main Groups

  • Format: Trim (removes spaces), Clean (removes non-printable chars), Case changes.
  • Extract: Pulls text based on length or delimiters (like @ in emails).
  • Number Column: Mathematical operations and rounding.

? Use Cases

  • Fixing messy Excel names with leading/trailing spaces.
  • Extracting usernames from email addresses.
  • Converting mixed-case city names to standard UPPERCASE.
  • Cleaning non-printable characters from web-scraped data.

? Text Transformation Lab

Try these standard Transform functions on the "messy" sample data below:

Original / Messy Data Transformed Result
  Rahul   -
anita@gmail.com -

✅ Tips & Best Practices

  • Trim vs. Clean: Always use Trim for visible spaces and Clean for invisible system characters.
  • Perform Early: Do these transformations in Power Query rather than using DAX calculated columns to save memory.
  • Step Naming: Rename the auto-generated "Trimmed Text" step to "Removed Spaces from Name" for better documentation.
  • Check Nulls: Transformations on null values remain null; check your data quality before applying extracts.

? Try It Yourself

  1. Import the Customer CSV and select the CustomerName column.
  2. Go to the Transform Tab → Format and click Trim.
  3. Select the Email column → Extract → Text Before Delimiter and enter @.
  4. Select the City column → Format → Uppercase.