--步骤一：导出分数表的数据
exp newdream/dream1234@tm file=c:\t56\score.dmp tables=(score);
--步骤二：删除表
drop table score;
select * from score;
--步骤三：将步骤一导出的表还原
imp newdream/dream1234@tm file=c:\t56\score.dmp tables=(score);
--步骤四：只删除数据，再次导入。如果表已经存在不允许导入
delete from score;
imp newdream/dream1234@tm file=c:\t56\score.dmp tables=(score);
imp newdream/dream1234@tm file=c:\t56\score.dmp tables=(score) ignore=y
