Why your Dataform incremental table keeps adding duplicates
Your Dataform incremental table keeps adding duplicates? A NULL in the merge key could be why. Here’s how it happens with GA4 and how to stop it.
Elisa Liu3 Nov 2026
Blog
Dave Beatty8 November 20214 min read

When working with a consultancy firm, the typical benefits you might look for are likely some combination of relevant expertise and available resources. You may be looking to level up the skills within your business, or you may be looking to ease the pressure on a stretched team.
As Analytics Consultants, we have a wealth of specialised experience that we can bring to bear on your business. However, working with a consultant also brings a hidden benefit that you may not have thought of: the superpower of objectivity.
Let me explain.
When it comes to your company’s data strategy, you can play it safe, or you can place some big bets. The currency you are using in this wager is your professional reputation and internal standing.
Small, iterative changes will most often lead to small, iterative results. These are safe, they're unlikely to rock the boat or get you in trouble, and will give you a solid basis for any career.
But, what if you want to take something to the next level, quickly? What if you want to revolutionise your company's use of reporting? To do this, a lot of change will need to happen quickly. You might want to implement GA4, to build a data warehouse, and pivot away from a whole load of Excel reports that have "worked just fine" for several years.
By doing something dramatic, you could genuinely catapult your company’s efficiency and profits by taking control of data. You could roll out a whole suite of reports that fundamentally improve the way decisions are made across the business. You could be the author of this change – you could reap the benefits.
But, it might not work. It might be delayed, it might turn out to be more complex than you thought, reports may break, stakeholders may be upset. It can be easy to see why now is not the right time, why it’s better to put this on the backburner for the time being. Just get a few reports out – let’s think about it next year.
Join marketing, customer and product data with tested models and documentation your team can use. Start with the sources needed for your question.
How do I know this? I’ve worked as an in-house analyst. These have been my thoughts, my worries, my concerns. Knowing I could be doing something better, but not quite knowing how to get there.
It’s not just me. Every team member at Measurelab has previously worked in an analytics function in an agency or as an in-house analyst. We get it. And this is where our superpower of objectivity can help.
As a consultant, because it’s not my business, it’s not my team, and it's not my boss who will give me a hard time, I'm less susceptible to the thoughts and niggles that might lead me to talk myself out of a bolder solution. I can objectively look at the most effective path to level up your data strategy without considering the risks in the same way.
To be clear – I am not implying that I don’t care about the risks to my clients’ businesses or that I make flippant decisions or recommendations – I care very deeply about the work I do. And that’s precisely it. I care about the work.
Driving change like this is a high stakes game – it's a high reward, but it’s a high (professional) risk. As Analytics Consultants, we're able to suggest higher risk solutions because it's not our entire job or career on the line.
We're also able to shoulder this risk on behalf of our clients – they can suggest something risky that might disrupt things internally because it's us recommending it. If it goes wrong or doesn't work well, then it’s quite rightly our responsibility to fix it.
Working with Measurelab isn’t just about technical skills or experience in software – it’s about gaining access to someone who can see things from a degree of distance and act as a lightning rod for risk.
It’s about gaining access to the superpower of objectivity.
Join marketing, customer and product data with tested models and documentation your team can use. Start with the sources needed for your question.
Bring data to connect, a question to investigate or something to fix or build. We can agree a focused scope directly.
Your Dataform incremental table keeps adding duplicates? A NULL in the merge key could be why. Here’s how it happens with GA4 and how to stop it.
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