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alter table novel.novelsort add unique(name);

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select a.id,a.ip,a.creationTime from myTable a right join (

select max(id) id from myTable group by ip) b on b.id = a.id

where a.id is not null

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select a.* from myTable a right join (

select max(id) id from myTable group by ip) b on b.id = a.id

where a.id is not null