删除重复项

Question

从这个SO POST Finding Duplicates，我该如何删除重复项。

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 

Answer 1

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，请访问：

http://www.cyberciti.biz/faq/howto-removing-eliminating-duplicates-from-a-mysql-table/