I am aware of deployment process from Ecplise. but need to know more and not finding good documentation.

1. Test class is taking which data QA or Prod ?

2. if it is taking Prod data then it is not possible to see information in the log.

3. if it is taking data of Prod then it is not required to Fix errors in the QA / Test environment.

4. Not able to find good document on this.

Please suggest it is urgent.