logical adj. 1.逻辑的,逻辑上的;逻辑学上的。 2.合乎逻辑的。 3.逻辑上必然的。 logical constants 逻辑常词[常项]。 logical necessity 逻辑的必然性。 a logical argument 条件分明的论证。 a logical process 合理的程序,合乎逻辑的[必然的]过程。 the logical result 必然的结果。 adv. -ly ,-ness n.
In order to query " the data in multimedia database , we present logical query lancuaee based on multimedia - instance model and demonstrate the applications of the logical query language by some examples 为查询多媒体数据库中的数据,我们给出了基于媒体实例模型的逻辑查询语言,并举例说明该语言的应用。
Many mature technologies on this level have been brought out , such as the relational algebra law , the improved logical query plan , the cost estimation of operation , the selective plan based on cost and order of joint , etc . although many methods have been tried out , no remarkable result or noteworthy technology has come to reality because of complexity of data decomposition and network effects 例如,从物理查询计划的底层磁盘输入输出到语法分析阶段的语法分析树、用于改进查询计划的代数定律、逻辑查询计划的改进,以及操作代价的估计、基于代价的计划和连接顺序的选择等全过程,都进行了不懈的努力。在这方面的研究已经非常成熟。