Um protocolo de controle de concorrência não restritivo para bancos de dados cooperativos.

Abstract

With respect to the cooperative applications, the ACID properties (Atomicity, Consistency, Isolation, Durability) seems very restrictive, because this kind of applications have characteristics as a great interactivity, a long time alive etc. To give effort to these characteristics, has emerged extensions of conventional transaction model, as the different cooperative transaction model. This dissertation particularly is based in a cooperative transaction model, called "Cooperative Unit Model", MUC. Also presents the more expressive concurrency control protocols for non-conventional transactions which give effort to elaboration of a concurrency control protocol for transactions under "the cooperative unit model". This protocol, is divided in two great rules: one to gain a lock in a IS-A or IS-PART-OF hierarchy and other to define lock inheritance and transference between transactions in a cooperative unit.