An Active Database Management System (ADBMS) is a conventional Database Management System (DBMS) extended with the capability to execute Event-Condition-Action (ECA) rules, which allow defining actions to be executed in response to events. Triggers, as defined in the SQL3 (Structured Query Language) standard, are typical examples of ECA rules. However, despite the importance ADBMSs attach to these rules, they usually provide limited support for business rules implementation, which go beyond the restricted view of just imposing integrity constraints on data, since they determine the modus operandi of a business, which can be very complex. This paper analyzes the SQL3 support for specifying business rules in order to identify limitations related to the definition of each rule type frequently used in information systems.
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