GA4 truncates page names to a maximum length of 300 characters. In this article: the details, how to measure the problem, and a workaround.
Making sense of Page Views in GA4
What is collected in the GA4 page_view event? A tip on how to deal with url parameters, and a cliffhanger about Content Grouping.
Session modeling in BigQuery SQL (using GA4 data and a trip to Paris)
What is a session? And how can I use SQL to express that.