The Theory of Active Databases vs. The SQL Standard

The concept of triggers has been used for almost thirty years. But taking into account the fact that the active database theory kept developing during the years, it is even more and more obvious that existing database management systems do not keep the pace with the theory i.e. there is an obvious gap between the theory and the practice. The paper deals with the theory of active databases; we will show what has been done in the theory, what are the lacks of some existing database management systems, and what defines the SQL 2003 standard in that context.