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Mysql 删除重复项_Mysql - Fatal编程技术网

Mysql 删除重复项

Mysql 删除重复项,mysql,Mysql,从这篇SO文章中,我如何删除重复的内容 SELECT firstname, lastname, list.address FROM list INNER JOIN (SELECT address FROM list GROUP BY address HAVING count(id) > 1) dup ON list.address = dup.address 只需使用DISTINCT关键字: SELECT DISTINCT firstname FROM list; 如果任何输出是

从这篇SO文章中,我如何删除重复的内容

SELECT firstname, lastname, list.address FROM list 
INNER JOIN (SELECT address FROM list 
GROUP BY address HAVING count(id) > 1) dup ON list.address = dup.address 

只需使用DISTINCT关键字:

SELECT DISTINCT firstname FROM list;
如果任何输出是重复的,mysql将删除它们

有关DISTINCT的更多文档,请点击此处:


不知道为什么要继续编辑它,不清楚你想要什么。如果您希望删除重复的行,DISTINCT将解决这个问题。您的意思是“如何从基表中删除重复行”还是“如何确保SELECT的输出中没有重复行”?这是两个截然不同的问题。第二种可能更好地称为“消除(结果集中的)重复项”,因为DELETE具有更改表的含义。