Campaign data in Google BigQuery was not provid to us in the early years of the tool and it was not until they were incorporat that the fields were creat in BigQuery. These data fields have exist since the day:
Before that date, not only do
You not have the campaign data, but the fields and records in BigQuery relating to the ” last click ” do not even exist in the tables.
If you have a BigQuery account with GA4 export, try it yourself:
Load your events_20240717 table (July 17) and you will see how the data appears in the schema tab as in the image above. Now load your events_20240716 table and you will see that those fields do not exist.
What does this detail mean? Well, if we are going to create campaign reports bas on Google BigQuery, we will never be able to extract data ig database prior to July 17, 2024. You would do well to even add to your queries the extra rule of never allowing data prior to that date to avoid problems and inconsistencies.
Whatever you want to filter
What if I want to create a campaign report with data prior to that date?
Well, I’m sorry to say that you’ll have to which one is more worth a try in march 2022 model the data yourself. Yes, BigQuery’s last click data is great, but when you want to run reports from early 2024 or, worse yet, when you want to create a YoY in 2025, you won’t be able to do so with this data.
For these applications
You will ne to create a query that is capable of extracting the users and sessions from your events. Locate the campaign changes in them bas on the values of mium, source, etc. and create an indirect last click attribution (informing the direct one with usa data data from the user’s previous campaign) that resembles the real one from Google.