Database management, Oracle Flame Graph for quick identification of Oracle bug 12.06.2015 by Oracle Team By Franck Pachot . Most of my performance stores start with a screenshot of Orachrome Lighty my preferred tool to have a graphical view of the database performance, in Standard and Enterprise Edition without any options:(…)
Database management, Oracle An alternative to DBA_EXTENTS optimized for LMT 12.06.2015 by Oracle Team By Franck Pachot . This is a script I have for several years, when tablespaces became locally managed. When we want to know to which segment a block (identified by file id, block id) belongs to, the DBA_EXTENTS view(…)
Database management, Oracle Oracle memory advisors: how relevant ? 12.06.2015 by Oracle Team By Franck Pachot . Do you look at memory advisors? I usually don’t but I still show them during the performance tuning workshop because there is no easy way to get an idea about memory sizing. This morning, while(…)
Database management, Oracle How to disable a SQL Plan Directive permanently 12.06.2015 by Oracle Team By Franck Pachot . In 12c you will see a lot of SQL Plan Directives. Some are useful to get better execution plans, but some will trigger too much Adaptive Dynamic Sampling and that can become a big overhead,(…)
Database management, Oracle Convert a snapshot standby to a new database 12.06.2015 by Oracle Team By Franck Pachot . A snapshot standby database is a nice solution when you want a temporary copy of the primary where you can do whatever you want (test a bug fix for example) and then convert it back(…)
Database management, Oracle 12c Dynamic Sampling and Standard Edition 12.06.2015 by Oracle Team By Franck Pachot . 12c is coming with more dynamic sampling, now called dynamic statistics and using the new Adaptive Dynamic Sampling algorithm. The goal is to have better estimations and better estimations gives better execution plans. However, this(…)
Database management, Oracle How to import SQL Plan Directives 12.06.2015 by Oracle Team By Franck Pachot . Today I’ve presented SQL Plan Directives at the SOUG Romandie event. I had a question about the import/export of directives by Data Pump. The idea is that a lot of testing has been done on(…)
Database management, Oracle DBA_SQL_PLAN_DIRECTIVE.LAST_USED 12.06.2015 by Oracle Team By Franck Pachot . If you have read Matching SQL Plan Directives and queries using it then you know how to use the ‘+metrics’ format of dbms_xplan. 21:49:54 SQL> explain plan for select distinct * from DEMO_TABLE where a=0(…)
Database management, Oracle List all RMAN backups that are needed to recover 20.05.2015 by Oracle Team By Franck Pachot . This blog post is something I had in draft and Laurent Schneider blog post reminds me to publish it. With the right RMAN configuration you should not have to managed backup files yourself. The(…)
Database management, Oracle Variations on 1M insert (6): CPU Flame Graph 18.05.2015 by Oracle Team By Franck Pachot . If you followed the 1M rows insert variations, you have seen how something simple brought me into an investigation with the latest tools available to see where the time is spent. When the time is(…)