I'm having an issue in Looker Studio, I'm trying to replicate a custom channel grouping and found the data was heavily skewed compared to GA4, so I've stripped it down and found where I believe the issue is. However, I've replicated the custom grouping arguments from GA4 as exactly as possible.
Below is what I'm replicating: [GA4 Conditions [1]: https://i.sstatic.net/YkKnW.png
What I've tried so far:
WHEN (Session default channel group = "Paid Search" OR
Session default channel group = "Cross-network")
AND NOT REGEXP_MATCH(Campaign,"((?i).*youtube).*")
THEN "Paid Ads"
ELSE "other"
WHEN REGEXP_MATCH(Default channel group,'Paid Search') OR
REGEXP_MATCH(Default channel group,'Cross-network') AND NOT
CONTAINS_TEXT(Campaign,'youtube') OR NOT
CONTAINS_TEXT(Campaign,'YouTube') THEN 'Paid Ads'
WHEN (Session default channel group = "Paid Search" OR
Session default channel group = "Cross-network")
AND NOT REGEXP_MATCH(Campaign, ".*(?i)(\\byoutube\\b).*")
THEN "Paid Ads"
ELSE "other"
When I add the NOT statement, it heavily skews the data in Looker Studio and does not compare to the GA4 data even though the conditions are replicated.
I've searched around but I can't seem to find a reason behind this and I feel like I may be missing something obvious, so I wanted to ask if anyone had any ideas.
It's a simple mistake where I'm cross-checking 'Session default channel grouping' against 'Campaign' and not 'Session Campaign'.