ANBOB™

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..

一个充满外键的表中DML，因为验证的原因会浪费很多额外时间，如果在确保数据的合法性的前提下先禁用外键约束，操作完后再启用，可以提高你的DML速度，下面一个procedure启用/禁用表上的全部外键。

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

–Tom Kyte’s printtab code
比如一个查询的列很多，在命令行窗口下看的很乱，就可以用tom的printtab转换成列打印出来

这两天一个库因操作了基表的dictionary出错，测试一下正常的drop tablespace做了哪些操作

—- Error Stack Dump —–
ORA-00600: 内部错误代码, 参数: [kghrcdepth:ds], [0x7FFE37407008], [], [], [], [], [], [], [], [], [], []
—– SQL Statement (None) —–
Current SQL information unavailable – no cursor.

前天有网友问题这个问题，今天测试一把，需求应该是如果producre存储过程运行出错，可以写错误日志到OS的文本文件，这样系统管理员就可以看到，无需分配数据库权限.

Verify that your KEEP pool is sized properly to cache frequently referenced tables and indexes. Moving frequently-referenced tables and indexes to SSD or the WriteAccelerator will significantly increase the speed of small-table full-table scans.

ORA-39083: Object type INDEX failed to create with error:
ORA-30032: the suspended (resumable) statement has timed out
ORA-01659: unable to allocate MINEXTENTS beyond 59 in tablespace ICMETBS
ORA-39125: Worker unexpected fatal error in KUPW$WORKER.UNLOAD_METADATA while calling DBMS_METADATA.FETCH_XML_CLOB

investigate moving your high-write datafiles to a smaller data buffer to improve the speed of the database writer process.

“Consistent gets – examination” is different than regular consistent gets. It is used to read undo blocks for consistent read purposes, but also for the first part of an index read and hash cluster I/O

java 读取文件，截取每行字符串