Postgresql 12 体系结构 Study 001 Tips
Oracle Exawatcher Tips

Oracle Restore 11g/19c Tips
Oracle Parallel Tips
Oracle 10046 event Tips
Oracle Hugepage Tips
Use the hugepages_settings.sh to recommond vm.nr_hugepages.
Oracle AWR delete Tips
Check SYSAUX’s contents.
How to clear history AWR reports in sysaux tablespace?
Use the following enviroments.
[oracle@ora7 ~]$ sqlplus / as sysdba
SQL*Plus: Release 19.0.0.0.0 - Production on Tue Apr 7 16:20:24 2020
Version 19.3.0.0.0
Copyright (c) 1982, 2019, Oracle. All rights reserved.
Connected to:
Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
Version 19.3.0.0.0
SYS@orcl> !cat /etc/redhat-release
Red Hat Enterprise Linux Server release 7.6 (Maipo)
SYS@orcl>
Github SpeedUp Tips
Markdown Tips
Oracle Flash Cache Hit Tips
Ref:
Oracle Database 11g Release 2に関する10の重要なこと – askTom Live -
Point8: Flash Cache 【Database Smart Flash Cache】
現在のところフラッシュキャッシュはOracle Enterprise LinuxとSolaris版(SPARC/x64)のOracle Database Enterprise Editionのみで使える機能です。
また、Oracle Exadataに実装されているExadata Smart Flash Cacheと混同してしまう方がいるかもしれません。
ここで説明したフラッシュキャッシュ(Database Smart Flash Cache)は、Oracle Exadataのそれとはまったく別の、独立した機能です。データベース・サーバー上でバッファキャッシュとともに利用するもので、ストレージレベルの機能ではありません。
Oracle Import Error Hit Tips
Export dumpfile from Oracle db 12.2 and import dumpfile to Oracle 12.1.
There was the following errors in import command.
ORA-39126: KUPW$WORKER.MOVE_DATA [TABLE_DATA:"XXX"."YYYYYYY"]
ORA-39096: METHOD
ORA-06512: "SYS.DBMS_SYS_ERROR"
ORA-06512: "SYS.KUPW$WORKER",
Command eg.
Export command:
expdp <user>/<password> SCHEMAS=<schema> DIRECTORY=<dir_dump> DUMPFIE=<dump_file> LOGFILE=<logfile_12.1.log> VERSION=12.1
Import command:
impdp <user>/<password> SCHEMAS=<schema> EXCLUDE=USER DIRECTORY=<dir_dump> DUMPFILE=<dump_file> EXCLUDE=STATISTICS LOGFILE=<logfile_12.2.log>
Reference:
Unable To Import Table Using DataPump Import (IMPDP) And Hitting ORA-39126 And ORA-39096 Errors (Doc ID 2193782.1)
To resolve the errors prior 12.2, apply Patch 20056333 and run post-installation step:
1. Navigate to the <ORACLE_HOME>/OPatch directory:
$ cd <ORACLE_HOME>/OPatch
2. Install the SQL portion of the patch by running the following command:
$ datapatch
Have a good work&life! 2020/03 via LinHong
Oracle 19c Poor Performance With DataPump Tips
Poor Performance With DataPump Export On Large Databases (Doc ID 473423.1)
Data Pump Export Hanging In RAC At ESTIMATE Phase And Slow Performance (Doc ID 1948926.1)