数据库问题

create temporary table tmp as SELECT test.name name,test.age age from test GROUP BY test.name,test.age HAVING count(*)>1; delete from test where EXISTS (select * from tmp where test.age=tmp.age and test.name=tmp.name); 根据楼主的语句改的。可行。

create table test( name varchar(10) not null, age tinyint not null )charset=utf8; insert into test values("张三",22),("张三",22),("李四",23),("王五",24); create temporary table tmp like test; insert into tmp select * from test group by test.name,test.age having count(*) = 1; drop table test; create table test like tmp; insert into test select * from tmp; 只想到了这个笨方法。 不知道有没有更简单的。

select distinct * into tmp from tableName   （得到无重复记录的表tmp） drop table tableName   select * into tableName from tmp drop table tmp 网上搜到这个做法，可以吗

就算知道这么多命令，电面怎么口述回答啊?

我也被招银问过这个问题

为什么招银喜欢问sql语句

根据rownum

建立唯一索引就可以了