Connecting & cleaning data

Connect to a source

Click Get data and pick a source — Excel, CSV, a database, a web page. Power BI imports a copy and remembers the connection so you can refresh later.

Power Query: clean before you model

After connecting, the Power Query Editor opens. Every step you apply here is recorded and re-run on each refresh — so you clean once, and it stays clean.

The transforms you'll use most

• Set correct data types (dates as dates, numbers as numbers).
• Remove unneeded columns and blank rows.
• Split or merge columns.
• Filter out rows you don't need.

Good habits here save hours later. A clean, well-typed table makes every measure and visual simpler.

This page is a free preview. The rest of the guide — modelling, DAX, and sharing — is part of the paid guide.