In this paper,we describe an e-learning tool that we have developed to assist University students studying various modules on database systems. We use the acronym DTST (viz. a learning tool for Database Transaction Schedule Testing) to refer to our learning tool. DTST enables students to actively construct their own learning environment, it can respond in an individualistic way to student input, and it has a built-in web interface that makes it widely accessible. Field tests conducted on DTST suggest that it provides students with a different and valuable type of learning experience that traditional methods do not provide.