Problem Description Peer-to-peer(P2P) computing technology has been widely used on the Internet to exchange data. A lot of P2P file sharing systems exist and gain much popularity in nowadays. Let's consider a simplified model of P2P file sharing syst
相关知识: db file sequential read 单块读 optimizer_index_cost_adj 这个初始化参数代表一个百分比,取值范围在1到10000之间.该参数表示索引扫描和全表扫描成本的比较.缺省值100表示索引扫描成本等价转换与全表扫描成本. 模拟实验 创建表(插入数据)和索引 create table test as select * from dba_objects; insert into test select * from test; create ind