When a group of authors collaboratively edits interrelated documents, consistency problems occur almost immediately. Current document management systems (DMS) often lack adequate facilities for consistency management. We extend traditional DMS by explicit formal consistency rules. In con-trast to many other approaches, we permit inconsistencies and present the consequences to the user, which is vital for flex-ible document management and information management. Based on a novel semantics our tools pinpoint inconsisten-cies precisely. In this paper we focus on a key issue: efficient techniques for consistency rule evaluation. Our strategy is known from databases: (1) static analysis characterizes and simplifies con-sistency rules, (2) at run-time rules are evaluated incremen-tally. The major differences to databases are that we con-sider informal documents and explicitly allow inconsisten-cies. Consequently, we do not have formal update descrip-tions and cannot rely on consistency prior to updates. This makes incremental consistency checking a real challenge. The contribution of this paper is to incrementally evalu-ate consistency rules in the presence of previous inconsisten-cies. We have implemented our techniques in a revision con-trol system. Our experiments show that efficient incremental evaluation provides the key to making our approach viable.
Scheffczyk et al. (Tue,) studied this question.