We propose a new method for generating for (view) updates in deductive databases. The method augments the deductive database schema with a set of transition and internal events rules, which explicitly define the database dynamic behaviour in front of a database update. At transaction-design-time, a formal procedure can use these rules to automatically generate parameterised transaction programs for base or view-update transaction requests. This is done in such a way that those transactions will never take the database into an inconsistent state. In this report we extend a previous version of the method by incorporating existentially defined rules, and formalising their treatment. Within this context, synthesis outputs and processes are provided. The method, implemented in Prolog using meta-programming techniques, draws from our previous work in deductive databases, particularly in view updating and integrity constraint checking.