We show that database schema validation and update processing problems such as view updating, materialized view maintenance, integrity constraint checking, integrity constraint maintenance or condition monitoring can be classified as problems of either abductive or deductive nature, according to the reasoning paradigm that inherently suites them. This is done by performing abductive and deductive reasoning on the event rules (Olivé 1991), a set of rules that define the difference between consecutive database states. In this way, we show that it is possible to provide methods able to deal with all these problems as a whole. We also show how some existing general deductive and abductive procedures may be used to reason on the event rules. In this way, we show that these procedures can deal with all database schema validation and update processing problems considered in this paper.