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Oracle 12.1.0.2: Wait event histograms in μs

By Franck Pachot . When an Oracle Database spends a high percentage of its DB time in User I/O, I usually check the wait event histograms in order to see if the storage system is working well. But today,(…)

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(…)

Backup a SQL Server database from On-Premise to Azure

SQL Server database backup & restore from On-Premise to Azure is a feature introduced with SQL Server 2012 SP1 CU2. In the past, it could be used with these three tools: Transact-SQL (T-SQL) PowerShell SQL Server Management Objects (SMO) With(…)

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(…)

SQL Server Perfmon does not start automatically

I have recently used perfmon (performance monitor) at a customer site. I created a Data Collector Set to monitor CPU, Memory, Disk, and Network during one day. Then, I ran the monitor and I received a “beautiful” error message…(…)