ORACLE 去除重复记录
delete from tbl_talbe
where (col1,col2,col3) in
(select col1,col2,col3
from tbl_table
group by col1,col2,col3
having count(*)>1)
and rowid not in
(
select max(rowid)
from tbl_table
group by col1,col2,col3
having count(*) >1
)
相关文档:
Oracle学习:分区表和索引
http://tech.it168.com/a2009/0609/585/000000585998.shtml
什么时候使用分区:
1、 大数据量的表,比如大于2GB。一方面2GB文件对于32位os是一个上限,另外备份时间长。
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Last login: Mon Feb 8 14:13:19 2010 from 192.168.1.249
ipnet
-bash-3.00$
-bash-3.00$ ipnet
-bash: ipnet: command not found
-bash-3.00$ su - oracle
Password:
eastcsu: incorrect password
-bash-3.00$ eastcom
-bash: eastcom: command not found
-bash-3.00$ su - oracle
Password:
[oracl ......
1、su – oracle 不是必需,适合于没有DBA密码时使用,可以不用密码来进入sqlplus界面。
2、sqlplus /nolog 或sqlplus system/manager 或./sqlplus system/manager@ora9i;
3、SQL>connect / as sysdba ;(as sysoper)或
connect internal/oracle AS SYSDBA ;(scott/tiger)
conn sys/change_on_install as sysd ......
为防忘记,记录于下:
oracle 11gR2 : http://www.oracle.com/pls/db112/homepage,下载网址http://www.oracle.com/technology/documentation/database.html
oracle 11gR1 : http://www.oracle.com/pls/db111/homepage
oracle 10gR2 : http://www.oracle.com/pls/db102/homepage ......