What is Power Query?
Power Query is the data preparation engine built into Power BI, Excel, and other Microsoft tools. It connects to a data source, then lets you import, clean, reshape, and combine the data before it loads into a report or model. Every transformation is recorded as a repeatable step, so the same cleanup runs automatically each time the data refreshes.
What Power Query does
Power Query handles the work that happens between a raw source and a usable model:
- Connecting to sources: databases, files, ERP systems, and web services
- Cleaning: removing errors, fixing data types, filtering rows
- Reshaping: splitting and merging columns, pivoting and unpivoting, grouping
- Combining: appending tables or merging them on a key
Each action becomes a step in an ordered list, which means the transformation is transparent and rerunnable, not a one-time manual edit.
The M language
Behind the point-and-click interface, Power Query records every step in a functional language called M (the Power Query Formula Language). Most users never write M by hand because the interface generates it, but the underlying code can be edited directly for transformations the interface does not expose.
Query folding
One of Power Query’s most important behaviors is query folding. When the source supports it, Power Query pushes transformation steps back to the source system as a single query rather than pulling all the raw data and transforming it locally. Folding keeps refreshes fast and reduces load, which matters a great deal when the source is a large ERP database. Steps that cannot fold are processed by Power Query itself, so the order of steps affects performance.
Power Query vs ETL
Power Query is a form of ETL (extract, transform, load), scoped to the Power BI and Excel world. For smaller and mid-sized models it often replaces a separate ETL tool entirely. For large enterprise pipelines, it usually works alongside dedicated ingestion and transformation in the data platform, with Power Query handling the last mile of model-specific shaping.
Where Power Query fits an ERP reporting model
ERP data is rarely report-ready. Codes need decoding, tables need joining, and values need standardizing before a number means what a business user expects. Power Query is where much of that shaping happens on the way into a Power BI model. The challenge in practice is that hand-built queries multiply, and the same logic gets rewritten in every file. QuickLaunch addresses this by shipping pre-built models for JD Edwards, Vista, NetSuite, and OneStream where the connection and transformation logic is already built and governed, so teams are not rebuilding the same Power Query steps report by report.
Frequently asked questions
What is Power Query used for? Connecting to data sources and cleaning, reshaping, and combining data before it loads into a Power BI or Excel model.
What is the difference between Power Query and DAX? Power Query prepares and shapes data as it loads (the transform step). DAX calculates over the data after it is loaded into the model (measures and analysis).
What is query folding? When Power Query pushes its transformation steps back to the source as a single query instead of processing them locally, which keeps refreshes fast.
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