之前，我还真没想过用rownum来提高性能。至于用游标循环，倒是很简单。Avoid COUNT(*) Unless Count is RequiredConsider the following requirement:Get the ID for the company which matches specified name.If no match, display error.If more than one match, show list.If single match, [...]
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什么是MapReduce? Google的分布运算开发工具MapReduce，用于大规模数据集（大于1TB）的并行运算! [...] |
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