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Power BIPower QueryData Preparation

Power Query Cleanup

Does every source change create another Power Query problem?

A practical review of Power Query logic, resilience and maintainability — including the boundary between source, transformation layer and semantic model.

Start with what is actually happening.

  • Queries contain dozens of steps that are hard to follow.
  • Folder combinations break when a column changes.
  • The same transformations appear in multiple queries.
  • Refresh times keep increasing.
  • Nobody is sure whether transformations are still folding.

Good work starts with better questions.

01

Which transformations should stay in Power Query?

02

Which should move upstream?

03

Where is logic unnecessarily repeated?

04

How can the queries become more resilient to schema changes?

The scope follows the problem.

I do not force every engagement through the same checklist. These are the areas that may matter; the agreed scope determines how deep we go.

Query structure and dependencies

Query folding

Combine Files patterns

Schema drift and resilient column handling

Data types and transformation order

Repeated logic and staging queries

Parameters and environment-specific logic

Refresh implications and source-side opportunities

Something you can use after the conversation ends.

The output should help you make a decision, change a practice or move the work forward. It should not exist simply to prove that work happened.

01

Query Review

A clear view of the main complexity, resilience and performance issues.

02

Resilience Recommendations

Practical changes for handling common source and schema changes more safely.

03

Simplification Opportunities

What can be consolidated, parameterised or moved upstream.

04

Refactoring Example

A concrete example where seeing the improved pattern is more useful than reading about it.

05

Layering Guidance

A clearer answer to what belongs in the source, Power Query and the model.

Enough structure to make the work clear. Not so much process that the process becomes the work.

01

Context

We start with a short conversation about what is happening, what matters and what has already been tried.

02

Review

I analyse the relevant parts of the solution or operating model at the depth agreed for the engagement.

03

Prioritise

I organise observations around impact, risk and usefulness — not around how many issues I can find.

04

Walkthrough

We go through the findings together, challenge assumptions and discuss trade-offs.

05

Next step

You decide what happens next: implement internally, continue together or stop because the focused engagement was enough.

I keep the client-side time demand deliberately light. A focused assessment usually needs a kickoff conversation, access or materials, and a final review session. We agree the exact involvement before we start.

This is likely to help if...

  • Power Query has grown organically and is becoming fragile.
  • You combine files or heterogeneous sources.
  • You want to reduce maintenance and improve refresh behaviour.
  • The transformation logic should clearly be rebuilt as a broader data-engineering solution.
  • You only need a one-off data-cleaning script.

If the problem is real but the format is wrong, that is useful to know early. I would rather redirect the conversation than force the challenge into the wrong service.

Does every source change create another Power Query problem?

Bring me the problem, not a polished brief. A few sentences about what is happening and what you would like to change are enough to start.

Tell me what's happening

Send me a message.

You do not need a polished brief. Whether the topic is Power BI, Fabric, AI, team training, mentoring, coaching or simply a challenge that needs untangling, leave a few details and we can start from there.

SIGNALMESSAGECONVERSATION

AI & TRANSPARENCY

AI supports selected parts of my work — it does not replace my judgement, responsibility or relationship with the client.

I use AI tools for tasks such as research, organising information, structuring content and preparing materials. I treat AI as support for my work — not as an autonomous author or decision-maker. Anything I publish or use professionally remains my responsibility.

In coaching, I do not use AI to automatically assess, diagnose or make decisions about a client. AI does not replace attention, confidentiality or human responsibility for the coaching relationship.

AI may support the process. Human responsibility remains.