你需要使用 row_number() 要处理此问题：

select t1.*
from (select col, row_number() over (partition by col order by col) as seqnum
      from t1
     ) t1 left join
     (select col, row_number() over (partition by col order by col) as seqnum
      from t2
     ) t2
     on t1.name = t2.name and t1.seqnum = t2.seqnum
where t2.name is null;

注意：这将返回任意名称。sql表表示无序的集合，因此表中没有“第一”行，除非列指定顺序。如果你有一个订购的想法，那么就用它来订购 order by .
此外，这允许在 t2 所有这些都将从 t1 如果有的话。