By William Sescu Not too often, but sometimes you might run into a situation when you lose everything, your DB Files, your Controlfiles and even your spfile. In situations like that, you need to restore first your spfile, then your controlfile and then the rest. For restoring the spfile, RMAN has a chicken/egg issue. To be able to restore the…
By William Sescu My good old DEPT table always had 4 rows with 4 different departments. However, I have noticed that a new row was inserted into the DEPT table and the row 50 popped up, and I would like to know when it happened? Before: SQL> select DEPTNO, DNAME, LOC from DEPT; DEPTNO DNAME LOC ———- ————– ————- 10 ACCOUNTING…
By Franck Pachot . Short summary of this post is that rolling invalidation do not occur when you gather statistics on Global Temporary Tables in 12c that have session statistic scope (which is the default) and this may cause too many hard parses. I’m sharing all details and comments are welcome. Update28-OCT-16 I’ve written this having in mind a specific…
By Franck Pachot . I’m preparing some slides about PDB security (lockdown) and isolation (resource) for DOAG and as usual I’ve more info to share than what can fit in 45 minutes. In order to avoid the frustration of removing slides, I usually share them in blog posts. Here is the basic concepts of CDB resource plans in multitenant: shares…
By William Sescu RMAN persistent settings can be managed in two different ways. Via the RMAN interface – e.g. RMAN> CONFIGURE BACKUP OPTIMIZATION ON; Via SQL – e.g. VARIABLE RECNO NUMBER; EXECUTE :RECNO := SYS.DBMS_BACKUP_RESTORE.SETCONFIG(‘BACKUP OPTIMIZATION’,’ON’); There are several scenarios when it might be helpful to use the SQL way. I will show 3 of them: Automation Reset to default…
By William Sescu Oracle incrementally updating backups are used quite often because they are easy to setup and restoring a datafile is very fast. It is very fast because you are not really restoring a datafile, you are switching to the copy, in case something happens. But how do I switch back to the original destination with minimal downtime and…
By Franck Pachot . In a previous post I described the new V$SQL views about rolling invalidation. I did the example with dbms_stats which is able to do rolling invalidation since 11g. But more is coming with 12.2 as you can use rolling invalidation for some DDL. When you do some DDL on an object, dependent cursors are invalidated. On…
By William Sescu A lot of new features popped up with RMAN 12c, like Expansion of Multi-section support, or Simplified cross-platform migration and many many more. However, in this post I would like to highlight a small, but very helpful new feature which I demonstrated during my session at the SOUG day. The automatic datafile creation In earlier versions of…
By Franck Pachot . In a previous post I published a test case to show when a cursor is not shared anymore after a rolling invalidation. Basically the dbms_stats marks the cursor as ‘rolling invalid’ and the next execution marks it as ‘rolling invalid executed’. Looking at 12cR2 there is a little enhancement in V$SQL with an additional column displays…
By Franck Pachot . When 12.1 came out, the major issue we encountered after migration was related to the new adaptive features of the optimizer: automatic reoptimization, SQL Plan Directives and the resulting dynamic sampling. Of course, Oracle product managers listen to feedbacks, ensure to provide workarounds or fixes and make things better for next release. Let’s see what has…
By Franck Pachot . This morning during Gerald Venzl presentation of “What’s New for Developers in the Next Generation of Oracle Database” at Oracle Open World, one feature has been acclaimed by a full room: 12.2 show the end of identifiers limited to 30 characters. 12.1 We knew it would happen because in 12.1 all data dictionary views have 128…
By Franck Pachot . It’s official, Larry Ellison made the announcement at first keynote and the database product team at oracle has released the version and the documentation publicly. Oracle Database Exadata Express Cloud Service is the ‘Cloud First’ environment for 12.2 Documentation Documentation is there: Cloud > Platform > Data Management > Exadata Express The 12.2 new features available…
