In the aspect of excute model, this paper analyzed usual concurrency control protocol : two-phase locking, multiversion concurrency control and multiversion two-phase locking protocol, optimized conventional mv2pl protocol, and provided a transaciton model of active database 在執(zhí)行模型中,本文在對(duì)傳統(tǒng)執(zhí)行模型的研究的基礎(chǔ)上分析了常見的并發(fā)控制協(xié)議:兩段鎖協(xié)議、多版本協(xié)議和多版本兩段鎖協(xié)議。