“…The resulting value from missing the deadline is used to categorize the real-time transactions into three types, soft, firm, and hard. Missing a hard deadline results in an infinite penalty which has a fatal effect on the system, missing a firm deadline gives no value, while missing a soft deadline may leave some value in the computation for some time (Wang, Li-Wei & Yang 2011). Recently, the demand for real-time databases is increasing, many applications such as e-commerce, mobile communications, accounting, information services, medical monitoring, nuclear reactor control, traffic control systems, and telecommunications require real-time data support (Hamdi, Salem & Bouazizi 2013).…”