ANBOB™

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”

除了linux中长用的vmstat,iostat,top,sar等工具外有两组轻量的工具也值的推荐，
一个就是经典的IBM 的nmon+nmonanalyser
另一个是Collectl+Graphite

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..

Total updates 12.00
Total deletes 0.00
Total discards 0.00
Total operations 13.00
Total update collisions 12.00

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], [], [], []

在公司累脑子，出来奉献点儿体力，顺便也当散散心缓解一下，接了个苦差事，从9月20号开始出差浙江两周，最近也已经 […]

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], [], [], [], [], []

对于每个数据库不同级别的错误可以做不同的处理，如短信、邮件等

经常有同事提供一个好N个列的EXCEL让你关连数据库增加一列，不想让把excel那么多字段导入db，就可以利用伟大的excel 公式做到实现

有时总是忽略在列的顺序带来的性能开销，还有列的null值字段的位置,想理解这个问题要首先程序列数据是如何在block上存储的，并且是如何定位的？

目前机器通常都是多core CPU,单个进程未开并行只会在一个core上运行，未完全发挥多core的特性，有时在统计查询,DML,DDL时需要开启并行提高效率