September 2014

Recover from rm -rf deleted datafile in NOARCHIVELOG mode using BBED

2014-09-242014-09-24 by weejar zhang

A friend from QQ Group find me, he removed a online datafile from the his production database, but for as long as the database remains up. he re I take a demo to show recovery process. …

Identifying Shared Memory Segments for multiple database(Disable AMM) 标识某实例的共享内存段ID

2017-07-142014-09-24 by weejar zhang

有时oracle 实例异常终止，会导致oracle process killed,但是实例之前所分配的shared memory segments没有release, 而此时登录提示no login，而且本机还有其它实例在用无法kill 所有…

ORA-07445 [ACCESS_VIOLATION] [unable_to_trans_pc] [UNABLE_TO_READ] Troubleshooting

2014-09-172014-09-17 by weejar zhang

Today I to read a SR, saw a case , to face a ora-7445 internal error when open resetlogs database after do database recovery. So here I collected some ora-7445 [unable_to_trans_pc] [UNABLE_TO_READ] errors with frequently ways to Troubleshooting .

oracle 12c new feature: In-memory option VS in memory standard row-major

2014-09-172014-09-15 by weejar zhang

Oracle 12.1.0.2 发布引入了一系列的新特性，当然还有关注度非常高的ORACLE In-Memory Option,在内存中提供一种列级的存储，在OLTP中提供更好的性能，当然在Exadata中ORACLE已在存储级提供了列级的性能优化hybrid columnar compressed (HCC) format…

Where is stored Initialization Parameter(spfile) for PDB in Oracle 12c (PDB参数文件存在哪里)

2016-04-252014-09-12 by weejar zhang

12c引入的可插拔的数据库容器(Multitenant Database)框架，在CDB中容器中的有1个或多个(Pluggable Databases)PDB，同时有一些参数是可以在PDB级别修改，我们暂时称为PDB local parameter, PDB 级的参数对于PDB自身影响会覆盖(优先)从CDB继承的参数…

ORA-600 [kdBlkCheckError][X],[X],[38504] and ORA-600[4194],[],[] in 11.2.0.4

2020-06-242014-09-03 by weejar zhang

The Oracle Database is crashing down in few minutes as soon as we start the Database. DB 11.2.0.4 in linux single instance . it is in VMWare 6, Done a dynamic disk allocation before the problem occurred . then check alert log found ORA-600 [kdBlkCheckError] and ORA-600[4194] errors.