When considering your upgrade path to Oracle Analytics Server (OAS) there are a series of questions that can be helpful to weigh your options.
First consider your starting point, are you on 11g or 12c? If you are currently on 11g then you will need to be 220.127.116.11 or higher. At this point your only option from 18.104.22.168 is to compete an Out-of-Place upgrade to OAS.
If you are currently using 12c, then consider if your instance is functioning well. Do you have the desired/required patches? Are you experiencing unexplainable bugs, and/or missing functionality. If any of the above are true, this is a chance for a fresh start, best option is Out-of-Place upgrade to OAS.
Even if your current 12c instance is functioning well, make sure your current install has to proper folder structure. If your folder structure is not correct the In-Place upgrade is not going to work. See link for more information about OBIEE 12c folder structures. At this point best option is Out-of-Place upgrade to OAS.
If all is working well and folder structure is correct in the 12c instance, then we must be at 22.214.171.124.0 or higher. If not, upgrade to 126.96.36.199.0, then the In-Place upgrade to OAS is a viable option.
Below decision tree can be used to help understand path options:
Watch our Analytics Webinar REPLAY for more details on OAS.