ORACLE 数据库

删除重复记录
delete from acc a1
where rowid != (select max(rowid)
                   from acc a2
                  where a1.name = a2.name
                    and a1.age = a2.age)
分页

select a2.*
  from (select a1.*, rownum rn from acc a1) a2
where a2.rn > 1
   and rownum <= 2

Rownum 与 rowid 的区别

    select * from acc where rownum > 0  // 查出全部结果
  
   select * from acc where rownum >2   //查出0条记录
  
向数据库中插数据
      1) 创建表：
         CREATE TABLE acc
         (
              Id  NUMBER(8) PRIMARY KEY ,
              Name VARCHAR2(30),
              Age   NUMBER(3)
         )

     2) 编写.cvs 文件 c:\oraclexe\acc.cvs
          8,赵二,89
          9,不要脸,29

      3) 编写.ctl文件 c:\oraclexe\acc.ctl
          load data
          infile 'C:\oraclexe\acc.cvs'
          insert into  table acc
          fields terminated by ','
          (id,name,age)

      4) 运行
        cmd>sqlldr userid=X5/123456 control=c:\oraclexe\acc.ctl