A data event is a relevant state transition defined in an event schema. Typically, event schemata are described by pre- and post condition for a single or a set of

data item A data item describes an atomic state of a particular object concerning a specific property at a certain time point. A collection of data items for the same object at the same time forms an object instance (or table row). Any type of complex inform ...

s. In contrast to ECA ( Event condition action), which considers an event to be a signal, the data event not only refers to the change (signal), but describes specific state transitions, which are referred to in ECA as conditions. Considering data events as relevant

state transitions allows defining complex event-reaction schemata for a database. Defining data event schemata for

relational database A relational database is a (most commonly digital) database based on the relational model of data, as proposed by E. F. Codd in 1970. A system used to maintain relational databases is a relational database management system (RDBMS). Many relatio ...

s is limited to attribute and instance events.

Object-oriented database An object database or object-oriented database is a database management system in which information is represented in the form of objects as used in object-oriented programming. Object databases are different from relational databases which are ...

s also support collection properties, which allows defining changes in collections as data events, too.

References

{{DEFAULTSORT:Data Event Events (computing) Databases Database theory