Practically none.

Heresy and inquisition in the middle ages has been hugely misconceived in popular culture. It was not nearly as violent as thought, and the purpose, aim and nature of inquisition is far different what we might think.

The Church believed that heretics were generally uneducated, mis-guided laypeople who required education about their beliefs. The aim of inquisition was to teach heretics, get them to repent/serve penance, and to ultimately reconcile them with the church. They did not aim, nor want, to execute people - this actually went against Canon Law.

Executions would take place if the heretic continued to obstinately defend their heretical beliefs, i.e. if they refused to take penance and adopt Catholic orthodoxy and thus could not be 'saved'.

Then, the inquisitors would pass the case on to secular law courts, which would more often than not lead to execution. This means that technically the Church didn't execute anybody - secular law courts did.

Sources: Studying Medieval History at University, currently happen to be in a lecture by Professor Frances Andrews (BA, PhD (Lond.) FRHistS) about Inquisition in the Middle Ages! Knowledge from text sources mostly from the work R.I. Moore, J. Arnold and C. Ames.

Can you be more specific as to which church and which time period you'd like to hear about?