/*通过DOS导出导入数据*/
EXP zy_xfxxpt/[email protected]:1521/orcl file=E:ZY_XFXXPT.DMP
IMP zy_xfxxpt/zy_xfxxpt@orcl file=E:\ZY_XFXXPT.DMP full=y

/*清空表数据*/
delete from tablename

/*复制列数据*/
update tablename set create_user = lrr,create_time = lrsj,create_dept = lrdw;

/*删除主键*/
alter table tablename drop constraint prikeyName;

/*添加主键*/
alter table tablename add constraint prikeyName primary key(id);

/*查询表中id重复的数据*/
select id from tableName group by id having count(*) > 1;

/*复制表数据  新表已经存在时使用这个方法*/
insert into newTable(field1,field2,...)
select field1,field2,...
from oldTable