I seem to have misunderstood the question, so here is an update. Google will usually track any valid Urls. The two exceptions I can think of are more theoretical than a practical concerns.
- Some old browsers (I think IE6 and similar vintages) have a character limit for GET requests (2048 bytes IIRC), so very long links will not work, and this not be tracked correctly. For all practical purposes these browsers should be extinct by now
- A Google Analytics request is limited to 8096 bytes.The request has to transmit the document location as part of the payload, so if your URL is really massively oversizes (technically 8000 characters is ">900") this would not be tracked. Again, this is hardly a practical concern (unless there is a lot of other data, like e.g. Enhanced E-Commerce product impressions in that request).
Old (and probably irrelevant) answer:
Google Analytics does typically not track actions within emails, since email clients do not usually support javascript (there are implementations of email open tracking via "web bugs" linked to a script that does a measurement protocol request, but event that does not work particularly well).
If this is a link that points to your homepage the typical way to track this would be via utm parameters - i.e. you do not track the action within the email itself, but the result (the visit to your homepage).
UTM parameters (or "campaign parameters") are
- utm_medium - the kind of traffic (if it's paid advertising, banner ads, or in your case e.mail)
- utm_source - the specific vendor (e.g. "google" if the link is from a paid Google Ad, or in your case it could be the name of the department that sent out the mail)
- utm_campaign - your advertising campaign; in the case of a periodic newsletter this could be e.g. the number of the newsletter
- utm_term - you usually would not use that in an email, that's reserved for when a link is a result of a search (then you would insert the search term)
- utm_content - if you have multiple links with the same link target and campaign info you can add additional information (e.g. if you have the same link at the top and the bottom of your mail you could indicate the position here)
You cannot do anything dynamic, though - if you want to mark links with a specific character count you would have to do this within your newsletter programm and insert the number. GA would then be able to pick this up from the campaign parameters.
E.g. for your use case you might construct a target URL like
www.example.com?utm_medium=email&utm_source=my_department&utm_campaign=pda_mail&utm_content=<number of characters>
and then get the information from the Aquisition reports in Google Analytics.
If the links do not point to your own homepage you would need to set up an intermediate page that tracks the utm_parameters before it redirects to the intended destination.