Database management

SQL Server 2014: DBCC CHECKDB and ReFS support

Have you noticed an interesting behavior with SQL Server 2014 when you are running a dbcc checkdb command? If not, you should have a look at this blog post. I discovered it completely by accident during some tests. If(…)

SQL Server: DBCC CHECKDB does not detect corruption

During my audits at customer places, it still happens very often to find SQL Server databases with page verification option configured to “none”. I always alert my customers on this configuration point because it can have an impact on the(…)

PostgreSQL for Oracle DBAs – an introduction

Having worked for several years as an Oracle DBA, I decided to have a look at the PostgreSQL database and see how it functions in comparison to the Oracle Database. The “Enterprise DB” graphical installation of PostgreSQL 9.3 is(…)

PDB media failure may cause the whole CDB to crash

By Franck Pachot . Do you remember last year, when 12c arrived with multitenant, David Hueber warned us about the fact that a single PDB can, under certain conditions, generate a complete system downtime? We are beta testers(…)

SQL monitoring 12.1.0.2 shows adaptive plans

By Franck Pachot . In a previous post, I have described Adaptive Plans. Even if I prefer to show plans with the SQL Monitor active html format, I had to stick with the dbms_xplan for that because SQL(…)

Beyond In-Memory, what’s new in 12.1.0.2 ?

By Franck Pachot . It’s just a patchset. The delivery that is there to stabilize a release with all the bug fixes. But it comes with a lot of new features as well. And not only the one that(…)

Drilling down V$RECOVERY_AREA_USAGE

By Franck Pachot . In a previous post I used X$KCCAGF to get more information about reclaimable archived logs in FRA, because there is a bug in standby (not opened) databases where archivelog deletion policy is ignored. I(…)

Oracle EM agent 12c thread leak on RAC

By Franck Pachot . In a previous post about nproc limit, I wrote that I had to investigate the nproc limit with the number of threads because my Oracle 12c EM agent was having thousands of threads. This(…)

Master Data Services installation for SQL Server 2012

This posting is a tutorial for installing Master Data Services on your Windows Server 2012. Microsoft SQL Server Master Data Services (MDS) is a Master Management product from Microsoft, code-named Bulldog. It is the rebranding of the Stratature MDM(…)

Partial Join Evaluation in Oracle 12c

By Franck Pachot . Do you think that it’s better to write semi-join SQL statements with IN(), EXISTS(), or to do a JOIN? Usually, the optimizer will evaluate the cost and do the transformation for you. And in this(…)