It usually happens with huge data with aggregation incolved.
For sure aggregation at qlik level is different then that of database level. Its obvious it will take time.
I could think of below things
1) you can try by increase resources like RAM and CPU cores at server level.
2) If not, then try by processing yearly data separately and storing them in yearly qvds so that you have limited data to process.
Hope it help.
Hiiii, I also think that this hanging issue is due to enormous data you have stored, you store your data in spearate fields of Sql and also increase the processing speed of server. You may also check it can be a problem with the validation of connections. Further, you may also go through the interactive and resourceful online video tutorial:- http://www.youtube.com/watch?v=8olMt2AOUJ8