Wrong analytics integration. Does it destroy statistics?

Question

If I have a website with a structure like this:

 - www.example.xyz/ 
 - www.example.xyz/product1/
 - www.example.xyz/product2/
 - www.example.xyz/about/
 - order.example.xyz
...
----------
 - admin.example.xyz/
 - www.example.xyz/forum

And Google Analytics is only integrated on the sites above the line. In the examples below the line, the analytics code is not integrated.

And then a user enters the website at root level, browses the site, clicks a few links, moves between products and THEN click on a link to the forum(where analytics is not integrated). He browses through the forum a bit and comes back to the main page.

Would Google Analytics count this as a new session? Even when the time spent between going to the forum and coming back to the site was less than 30 minutes?

If yes, wouldn't this completely destroy all statistics(Bounce Rate, Sessions etc.)?

Answer 1

You need to know the definition of a session in GA (cf. https://support.google.com/analytics/answer/2731565?hl=en). A session is the measure of activities on your website within a given time frame. The session only ends on these conditions:

1. there is more than 30 minutes of inactivity at any one time,
2. it is the end of the day at midnight (relative to the time zone set in your time zone settings),
3. cookies are cleared by the user,
4. the user's first visit is attributed to one campaign, user then leaves and comes back under a different campaign

Assuming you have sub-domain tracking properly implemented, then if you are missing tracking code for pages of the same site, then the visits to those pages will not necessarily result in new sessions. The data just won't be tracked. You can verify this for yourself. Just read the client ID value in your cookie after arriving on your site, browse your site for a bit, LEAVE your site completely and within 30 minutes come back to your site, and check the client ID again. The value should be the same, meaning that the session is still attributed to the same visit as when you first arrived. So in other words, leaving your site would be the same as going to your page where the tracking code was missing. Your data would be reflective of that same scenario of leaving your site.