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
Mark Rochefort14 October 20202 min read

The new future version of Google Analytics has been announced - now branded as Google Analytics 4. Building on the "App + Web" property that was released last year, this sets the direction for Google Analytics going forwards. It is now the default experiences for all new properties and is where all product developments will be focussed.
Google Analytics 3, commonly known as Universal Analytics, was released in October 2012. This next product iteration for Google Analytics is a major step on from that - and has re-built the entire approach to implementation, reporting and analysis.
Bringing together insights across platforms and devices, at its heart are powerful machine-learning models, enabling predictions for things like churn rates and revenue. Such modelling will also be used to fill the gaps in data, caused by opt-outs and cookie blocks for example, in specific sets of data. Indeed, features such as "consent-mode" and "data deletion" directly address the need to provide a customer with greater control of their analytics data collection and management.
While Google Analytics 4 is a new version, the underlying paradigm has actually been around a while - and it is something we are very familiar with. Both in the App + Web property released last year and, since before that, when it was powering the analytics within Firebase (Google's mobile application framework). So, if you have seen Firebase or App + Web, you are likely to recognise the direction this is headed.
This is where Google are investing any future product improvements. Game changing features such as BigQuery export (something that was previously a Google Analytics 360 - i.e. enterprise - feature only), e-commerce reporting, Data Studio connectors and much more are rolling out as we speak! Google Analytics 3 will not be developed much further - to gain from any of these new features you should be looking to make the switch to Google Analytics 4. At the moment, we suggest this is done in parallel to your existing setup so you can reasonably compare and contrast between the versions.
Speak to one of our experts to find out more about how we can help you with this transition.
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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
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