Coupling modes for concurrent active rules

In general, the coupling modes may divide into immediate, deferred and detached modes in active database systems, but this classification doesn´t suffer to clearly separate various execution models in concurrent active rule system. The ambiguity had been exploited that the same coupling modes (e.g. immediate) have different semantics in various active database systems. To clear up this ambiguity, we classified the coupling modes into syn-coupling and asyn-coupling modes, according to the key issue, synchrony/asynchrony, in parallel programming language. Rule execution semantics for various coupling modes are distinctly defined. It is beneficial to implementation and usage of the active rule system. After graph-based rule system (E-RG) and its execution model, we show the various strategies to construct the syn-coupling and asyn-coupling modes in E-RG rule system, based on semantics for coupling modes