字面上的意思是,反键索引是以相反的键值顺序存储 Reverse Key indexes spread the distribution of index updatees across the index tree by reversing the data value of the index key . It's only useful for queries that contain equality predicates . Because lexically adjacent keys are not stored next to each other in a reverse key index , For every updation , Oracle need to search the whole index , it takes more time than normal B-tree index 其中一个用途是用正键索引可以用在诸如’abc%’这种查询 使用反键索引可以用在诸如’%abc’这类查询 _____ 发件人: ocp0531-bounce@xxxxxxxxxxxxx [mailto:ocp0531-bounce@xxxxxxxxxxxxx] 代表 陈旭 发送时间: 2009年6月29日 22:03 收件人: ocp0531 主题: [ocp0531] 关于index options 李老师,书上有句话A reverse key index has its key value bytes stored in reverse order. 这话不是很理解。。。能举个例子说明下么? _____ 200 <http://count.mail.163.com/redirect/footer.htm?f=http://gouwu.youdao.com> 万 种商品,最低价格,疯狂诱惑你