In this paper we present our approach towards a modularized database management system (DBMS) whose components can be adapted at runtime and show the modularization of a DBMS beneath the record-oriented interface as a first step. Cross-cutting concerns like transactions pose thereby a challenge that we answer with aspect-oriented programming (AOP). Finally we show the implementation techniques that enable the exchange of database modules dynamically. Particularly with regard to stateful components we define a service adaptation process that preserves and transmits the component's state. Categories and Subject Descriptors D.2.7 [Software Engineering]: Distribution, Maintenance, and Enhancement; D.2.11 [Software Engineering]: Software Architectures; D.2.13 [Software Engineering]: Reusable Software; H.2.4 [Database Management]: Systems General Terms Design, Management Keywords Adaptation, availability, service-oriented architecture, component replacement, modularity, migration