ANBOB

在两个表的JOIN 中，CBO总是会计算三种JOIN的连接方式的代价，分别为NL JOIN,SM JOIN,HA JOIN,三种JOIN对前后两表的我称呼还不一样，分别是NL JOIN :outer table,inner table,SM :firest table,second table,HA:build table ,probe table,Nested jOIN中的outer table又叫driver table…

今天问到了这个问题：impdp 如果不导入权限？看了下impdp参数没有了grants选项，看了些文档发现还是除了data dump 必需要在服务端执行个参数上还是有一定区别的

今天网友问到在安装crs时,OUI出现了这个错误
“The specified shared raw partition /dev/raw/raw1 may not have correct permission”

SELECT p1 “file#”, p2 “block#”, p3 “class#”
FROM v$session_wait
WHERE event = ‘read by other session’;

Begin Snap: 18125 20-Apr-12 11:01:00 337 1.0
End Snap: 18126 20-Apr-12 12:00:28 490 1.0
Elapsed: 59.46 (mins)
DB Time: 12,979.44 (mins)

Start Oracle ASM library driver on boot (y/n) [n]: y
Scan for Oracle ASM disks on boot (y/n) [y]:
Writing Oracle ASM library driver configuration: done
Initializing the Oracle ASMLib driver: [FAILED]
log:modprobe: FATAL: Module oracleasm not found.

[oracle@dev-db backup]$ exp icme3/icme3 file=icme3_20120409.dmp
. exporting sequence numbers
. exporting cluster definitions
EXP-00056: ORACLE error 932 encountered
ORA-00932: inconsistent datatypes: expected BLOB, CLOB got CHAR
EXP-00000: Export terminated unsuccessfully

when compile package body,
ORA-00600: internal error code, arguments: [qcsgpvc3], [], [], [], [], [], [], []

oracle 不允许truncate 一个启用外键引用的父表，因为truncate 不会触发任何trigger和任何constraint验证，当然它也不会关心子表是不是真的为空或是不是没有参照。

DBMS_SHARED_POOL 是从10.2开始提供的包，可以访问shared_pool中的对象，功能检查大于批定大小的对象，加入/移除shared_pool对象，11.1再完善..

sql>ALTER DATABASE OPEN;
ALTER DATABASE OPEN
*
ERROR at line 1:
ORA-01092: ORACLE instance terminated. Disconnection forced