Switching Majors after Transferring to a UC from CC- Possible?

I will be transferring to a UC from community college, I am wondering if it will be possible to switch my major after transferring? I would then start taking classes towards the new major.
I have heard this is difficult to do, and sometimes it will not be allowed.
Is this possible and is there a process in place to do this?
Thank you.

Depends upon the UC and the major.

@bulkpecos: It looks like you have already started another discussion on the same subject and have gotten plenty of good advice so why are you reposting again? If you do not like the advice given, posting the same question especially since you have not listed your current major and intended major and which UC’s you are targeting is an exercise in futility. Please clarify if you have made a decision on which major you want to purse and which major you are currently taking classes for at your CC.