SQL ordered by Version Count and Troubleshooting

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 parameter

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

RMAN-08137: WARNING archived log not deleted, needed for standby or upstream capture process

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”

推荐两组linux性能分析工具

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: Heap size nnnnK exceeds notification threshold (51200K)

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

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know more about dbms_job fails

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..

goldengate update collisions

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

sqlplus autotrace sql Statistics value全部为0

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

ora-600 [kcbgcur_9] internal error when ALTER DATABASE ADD SUPPLEMENTAL LOG DATA

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], [], [], []