已知一个person表,表中数据如下:需求是删除email相同的数据。

该问题是传统的数据去重问题,可以采用row_number() over进行排序筛选,这里不进行详细介绍。
再此介绍一个利用笛卡儿积的方法进行去重,该去重方法较为简单,现给大家进行介绍:
DELETE p1
FROM person p1,person p2
WHERE
p1.email = p2.email AND p1.id > p2.id;
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已知一个person表,表中数据如下:需求是删除email相同的数据。

该问题是传统的数据去重问题,可以采用row_number() over进行排序筛选,这里不进行详细介绍。
再此介绍一个利用笛卡儿积的方法进行去重,该去重方法较为简单,现给大家进行介绍:
DELETE p1
FROM person p1,person p2
WHERE
p1.email = p2.email AND p1.id > p2.id;
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