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DB2随机抽样的SQL
source link: https://www.lujun9972.win/blog/2020/04/10/db2%E9%9A%8F%E6%9C%BA%E6%8A%BD%E6%A0%B7%E7%9A%84sql/index.html
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DB2随机抽样的SQL - 暗无天日
DB2随机抽样的SQL
其实就是活用rand函数.
比如从数据库中随机抽取100条记录，那么可以这样做
select * from $table order by rand() fetch first $limit rows only
不过如果数据量大，这个运算量可以想象那是相当感人了。
再比如从数据库中随机抽取1%的记录，那么可以这样做
select * from $table where int(rand()*100)=0
2020-04-10
2020-04-22
linux和它的小伙伴 DB2 数据库
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