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By default, RMAN creates all backups as backup sets, on tape or on disk. You can change the default backup type for disk backups to be image copies using the CONFIGURE command. Backups to tape can only be backup sets.
同一实例下，不同用户之间的数据同步导入
1，exp from a user,imp to b user,
2,impdp network_link,不生成dump文件直接导入
…
Extent Header:: spare1: 0 spare2: 0 #extents: 4 #blocks: 32
last map 0x00000000 #maps: 0 offset: 2716
Highwater:: 0x02400391 ext#: 3 blk#: 8 ext size: 8
接上一篇，
如果丢失数据库默认表空间的任一数据文件，数据库会不会shutdown?
Your database is having two control files, three redo log file groups with two members in each group. Failure of which file would cause an instance to shut down
Your database is configured in NOARCHIVELOG mode. All the control files have been lost due to a hard disk failure but the data files are not lost. You have the closed whole database backup available to you…
UDE-00008: operation generated ORACLE error 28009
ORA-28009: connection as SYS should be as SYSDBA or SYSOPER
SQL> show parameter recy NAME TYPE VALUE ———————————— ———– —————————— buffer_pool_recycle string db_recycle_cache_size big integer 0 recyclebin string on SQL> alter system set recyclebin=off 2 ; System altered. SQL> show user USER is “SYS” SQL> conn anbob/anbob Connected. SQL> create table testdrop(id integer); Table created. SQL> desc testdrop Name Null? Type —————————————– ——– —————————- ID … Read more
flashback query 可以闪回以前的数据行，但不可以闪回alter table修改前的表结构,这点在11G推出的闪回表空间是一样的…
One of the database users accidentally deleted all the rows of a critical table and committed the delete at 1:30 p.m. …
Identify the two tablespaces whose data files are so critical that only a closed recovery is possible. (Choose two.)
在linux 上很容易查询 oracle的错误编码，得到提示、原因、及大概解决思路，但windows操作系统就没有办法应用oerr查询错误了，但是有群国外的哥们实现了在windows上使用oerr的方法
今天群里谈DUAL,网上找了点说明，DUAL表就像ORACLE的宝贝女儿，一直隐藏而众多人士又想了解靠近，我决定试一下，发现10G的dual表比9i有变动，也更加合理，话不多说，老风格动手吧
从表里提取汉字, 需要考虑字符集, 不同的字符集汉字的编码有所不同
这里以GB2312为例, 写一函数准确地从表里提取简体汉字.
在itpub上看到了这个方法，我修改了一下，修改后如下
SQL> delete test where id=1;
SP2-0544: Command “delete” disabled in Product User Profile
SQL> conn zwz/zwz;
Error accessing PRODUCT_USER_PROFILE
Warning: Product user profile information not loaded!
You may need to run PUPBLD.SQL as SYSTEM
一般向一个表插入数据时，为了提速用到append 提示，但有没有想过表上的索引是怎么维护的？
For a table to be recoverable using Flashback Drop, it must reside in a locally managed tablespace. Also, tables in the SYSTEM tablespaces cannot recovered using Flashback Drop regardless of the tablespace type.
Transportable tablespace feature introduced since Oracle 10g allowed a tablespace placed in a read only mode to be transported to another database and plugged in. However system and sysaux tablespaces were not transportable
Database mounted.
ORA-00313: open failed for members of log group 3 of thread 1
ORA-00312: online log 3 thread 1: ‘/u01/app/oracle/oradata/ORCL/onlinelog/o1_mf_3_5y4dgorl_.log’
ORA-00312: online log 3 thread 1: ‘/u01/app/oracle/flash_recovery_area/ORCL/onlinelog/o1_mf_3_5y4dgq04_.log’