生手求教；php sql找出最近相同内容的字段 用id相减输出差
新手求教；php sql找出最近相同内容的字段 用id相减输出差
php mysql数据库找出最近相同内容的字段，用它们的id相减输出差，例如：type字段，（id-1、字段内容5）；（id-8、字段内容9）；输出9-5的差。新手 详细的。谢谢 谢谢
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How does MySQL differ from Oracle?
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