Effect on existing site of importing Google data into new site

I have a site that is missing data from four months in the middle of 2019. (For whatever reason, the Matomo JS wasn’t running on the site during this period.) If I retain the existing site, and import google data for all of 2019 into a new site ID, will that import impact the existing analytics? I’m assuming that each pageview recorded is mapped to the site ID, so traffic from one site ID won’t affect another site ID, even if the hostnames are the same. I just wanted to confirm before I began the import.


The google analytics import cannot be merged witht the existing data and will always create a new site id.

That was my understanding. However, I’m now seeing data missing from my original site after I imported google data. Is it possible that importing data from google could somehow interfere with existing data for the same domain with a different site ID?

After seeing the data missing, I tried to invalidate the reports from the original site, but that doesn’t seem to have helped.

I’m still troubleshooting everything, but I think my issue is related to my raw data deletion settings. I believe I tried to invalidate reports beyond my retained raw data. If that’s the case, I’m going to try to change my raw data retention settings, partially restore old data from backups, and then recreate the reports. If I get stuck, I might open a new issue here.