have you check this article, in simple term qlikview is guided analytics whereas qliksense is self service analysis
(i.e end users can create their ad-hoc analysis by themselves with minimal IT support and qlikview fully IT driven)
Synthetic table and Synthetic keys gets created when there are more than one common fields between the 2 or more tables.
using below method we can avoid synthetic table & Key:
1) Removing fields (i.e Common fields causing synthetic & it's not required in data model we can simply remove it)
2) renaming fields using QUALIFY Statement (alias field name)
3) by creating autonumber/composite key
4) by creating a link table , joins and concatenating similar tables
for more details you can check this article,
p.s: if you further question apart from these two question. close this thread by marking helpful and correct.
after that open a new thread post. thanks