September 2010
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物化视图,索引,数据仓库

Materialized Views, 其实不是View。我觉得把它归类于Index可能还准确一些。
View在我们的印象里总是逻辑存在的。即使前面加上一个Materialized,我们只会觉得奇怪,干嘛要对View进行物化呢?
把它理解为一种特殊的Index未尝不可,况且,它与Index有一些相同点:
They consume storage space.
They must be refreshed when the data in their master tables changes.
They improve the performance of SQL execution when they are used for query rewrites.
Their existence is transparent to SQL applications and users…….