Abstract
On-line analytical processing (OLAP) systems deal with analytical tasks in businesses. As these tasks do not depend on the latest updates by transactions, it is assumed that the data used in OLAP systems are kept in a data warehouse, which separates the input from operational databases from the outputs to dialogue interfaces for OLAP. In the paper we describe how abstract state machines (ASMs) can be used to design OLAP systems. Based on the idea of separating input from output we model a ground model ASM for OLAP and discuss system quality by reasoning about this model.