专栏：ORACLE索引研究
[数据库] oracle索引重建到底会提高多少性能？ 工作中往往会观察到索引重建带来的空间释放和应用性能提升。空间释放比较容易理解，也非常容易度量，那么索引重建到底会对应用的性能有多少影响那？首先我们会问：索引重建为什么会带来性能的提升？毫无疑问，
[数据库] oracle索引重建到底会提高多少性能？
工作中往往会观察到索引重建带来的空间释放和应用性能提升。空间释放比较容易理解，也非常容易度量，那么索引重建到底会对应用的性能有多少影响那？首先我们会问：索引重建为什么会带来性能的提升？毫无疑问，这是因为索引重建后，与索引有关的io操作得到了降低。那么，索引io的降低在多大程度上影响了应用语句的执行效率？这恐怕需要具体问题具体分析了。 首先，我们来看一下多数情况下，索引重建的效果如何 SQL> ...
oracle index rebuild performace
joeadai 2013-11-22 13:51 阅读(1096) 评论(1)
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