Since ERP systems, like SAP, support the backbone operations of companies, their transaction logs provide valuable insight into the companies’ business processes. In SAP every transaction is stored and linked to relevant documents, organizational structures and other process-relevant information. However, the complexities and size of SAP logs make it hard to analyze the business processes directly with current process mining tools. This paper describes an ERP log analysis system that allows the users to define at a meta level how events, resources and their inter-relations are stored and transformed for use in process mining. We show how the system is applied to extract and transform related SAP transaction data for the ProM process mining tool.