however, the farther analysis in the paper indicates that the strategy of parameter configuration in current connection pool technique is static state with 1-order enactment while initializes connection pool without self-optimized adjustment according as the variety of application demand, the operation results of high use frequency database are not cached and users visit the same database independently . the multi-propose connection strategy cannot control the database operation for the same transaction and cannot ensure the acid attribute, etc . in according with the defections mentioned above, the service technique of self-optimized connection pool is presented in this paper and the composing structure for self-optimized connection pool is designed, then, some strategy in dynamic parameters adjustment, transaction management and data cache for connection pool is improved 然而,通过本文的研究分析,现有数据库连接池技术的参数配置策略是静态的,连接池初始化时进行一次设定,不能根据应用需求的变化而动态调整;连接池的核心管理机制中,没有对使用频率较高的数据库操作结果进行缓存,多个用户依然各自独立地完成相同的数据库访问;使用的连接复用策略无法控制属于同一个事务的多个数据库操作,不能保证事务的acid属性等。
(3 ) an ert experiment system is developed base on the new resistance measuring circuit . this system is entirely designed as a field-bus instrument . instructions are sent from the pc to execute some work such as parameter configuration, fault-checking and data-acquiring (2)基于该新型高速微弱电阻变化测量电路研制了一套完整的电阻层析成像系统,该仪表完全基于工业现场仪表模式设计,上位机通过rs232rs422总线向下位机发送指令完成故障检测、参数配置、数据采集等各种功能。