ANBOB™

有时需要参考一些隐藏参数值了解ORACLE内部的限制,在sqlplus 中使用show parameter 显示隐藏参数..

Session cursor caching does not mean that server process caches the whole SQL area in the PGA.It just means that Oracle does not release the cursor object when the same statement was executed more than 2 times in the same process…

今天看到一个案例，从10G升级到11GR2后cpu负载迅速上升，很快达到100%,通过OWI显示出现大量“Cursor: mutex S”事件，mutex S是发生在cursor cache上的序列化mutex

Oracle Management Agent 12c communicates only with Oracle Management Service 12c and not with any earlier release of Enterprise Manager

EM 12c在安装时和11EM相似，只是增加了Plug-ins 的选择，Plug-ins 和 Connectors做为GRID CONTROLE的扩展并增加了一些非oracle的产品整合为”Cloud”云管理包含DATABASE,Middleware,VM server

the cause:
bug,related to name resolution issues, bind buffer length, fine grained access control, cursor invalidation, or any of the other common structural or coding reasons for multiple child cursors

DB_FILE_MULTIBLOCK_READ_COUNT is one of the parameters you can use to minimize I/O during table scans. It specifies the maximum number of blocks read in one I/O operation during

When he tried deleting archivelog manually with RMAN on primary db host, he got following warning:

“归档日志未删除, 因为备用或上游捕获进程需要它”

Memory Notification: Library Cache Object loaded into SGA
Heap size 106084K exceeds notification threshold (51200K)
KGL object name …

When job execution fails, the SNP processes attempts to rerun the job one minute later. If this run fails, another attempt is made in two minutes and another in four minutes. The job queue doubles the retry interval until it exceeds the normal execution interval..

0 db block gets
0 consistent gets
0 physical reads
0 redo size
0 bytes sent via SQL*Net to client
0 bytes received via SQL*Net from client
0 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
62 rows processed

SQL> ALTER DATABASE ADD SUPPLEMENTAL LOG DATA;
ALTER DATABASE ADD SUPPLEMENTAL LOG DATA
*
ERROR at line 1:
ORA-00600: internal error code, arguments: [kcbgcur_9], [8388681], [25],
[100663296], [33554432], [], [], []

3 begin
4 hdl := dbms_datapump.attach(‘SYS_IMPORT_FULL_03′,’SYSTEM’);
5 DBMS_DATAPUMP.STOP_JOB(hdl,1,0);
6 end;

alter system set control_files=’+DATA/ANBOB/CONTROLFILE/current.260.793738081′,’+DATA/ANBOB/CONTROLFILE/current.261.793738087′,’+DATA/ANBOB/CONTROLFILE/current.276.793737555′ scope=spfile;

Control Seq=53995=0xd2eb, File size=594=0x252
File Number=0, Blksiz=16384, File Type=1 CONTROL
Logical block number 1 (header block)

数据文件如果有2g，先create一个大表占了1G,后来建了个几M小表，再把大表drop 掉加purge选项，向把数据文件resize到100M，往往会失败，在磁盘紧张的情况下，想知道数据文件最小值是多少？就要计算datafile HWM

其中有两个编号段比较特殊
1，错误编号-10000到-10999 不是真正的错误，是保留下来用于debug使用
2，错误编号-20000到-20999是自定义异常，错误信息最大2048B

HANG ANALYSIS:
==============
Open chains found:
Chain 1 : :
<0/1777/32406/0x5275fca0/13913/SQL*Net message from client>
— <0/1477/37455/0x5275e4e8/16043/enq: TX - row lock contention>

SQL> shutdown immediate
ORA-00600: internal error code, arguments: [3708], [910], [], [], [], [], [], []

Basically this error is raised because LGWR timmed out.

ksedmp: internal or fatal error
ORA-00600: internal error code, arguments: [keltnfy-ldmInit], [46], [1], [], [], [], [], []