Is it possible to add the node relationship as an option? I can imagine the node ID isn't stored in GA, but shouldn't it be possible to get the node ID via the path?
It's something I've fiddled with a little. A relationship in the usual way is impossible, because there's no way to "join" GA data with SQL data in a single query. I'm trying to find a way to execute two queries and combine the results before rendering, but Views isn't really designed for this.
Non-working patch attached with my experiment so for.
If you need this functionality now, my advice is to use a theme pre-process function to load the node data, or write your reports using google_analytics_api_report_data().
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