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Home > Database > Mysql Tutorial > sql 如何从百万条记录中删除某会员发布的N条记录-sql检索效率问

sql 如何从百万条记录中删除某会员发布的N条记录-sql检索效率问

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Release： 2016-06-07 17:49:35
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第一次执行，内存里没有缓存这些数据，需要从硬盘上读取，所以会很慢。第二次执行，数据已经进入了内存，就不需要从硬盘上读取，直接从内存里读，所以很快

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