如何从表的相同记录列表中获取一个唯一记录？表中没有唯一性约束

如何从表的相同记录列表中获取一个唯一记录？表中没有唯一性约束

任何一行都是第三行:-)

create table test(n int,name varchar(30));insert into test values(1,'yoko'),(1,'yoko'),(1,'yoko');select ROW_NUMBER() over(order by name) as ordinal, * from test;

删除“第三”行：-)

with a as(select ROW_NUMBER() over(order by name) as ordinal, * from test)delete from a where a.ordinal = 3

删除最后一行：

with a as(select ROW_NUMBER() over(order by name) as ordinal, * from test)delete from a where a.ordinal = (select MAX(ordinal) from a)