Clik here to view.
Measuring IOPS on XtremIO
Today, we can put our database on very efficient storage. EMC XtremIO is one of them. In this blog post, I’ll show how to look at the IO performance from Enterprise Manager, Orachrome Lighty, and...
View ArticleClik here to view.
Windows 10 – I tried and came back
I’ve tried Windows 10 one month ago, and I had to roll back because VirtualBox failed to create host-only interfaces. Today, it forced me to upgrade again, so I tried a little further… and finally...
View ArticleClik here to view.
dbi services at DOAG 2015
As in the past years, dbi services is present at DOAG, and our speakers give 8 session, as well as one full day training. We are looking forward to meet you there. Here is the program. Our Sessions The...
View ArticleClik here to view.
DataBase Cloud Service performance – Network
In previous posts, I’ve installed SLOB on the Cloud Services, measured IOPS and CPU. There’s another resource that is even more important in a cloud environment: network. Tuneling port 1521 over ssh...
View ArticleWaiting for row lock. But which row is locked?
When you are waiting on a locked row, the locked resource is the transaction that has locked the row. We have no information about which row is locked. Here is how to get it from V$SESSION. In a first...
View ArticleInvisible indexes: it’s online in 12c – even in Standard Edition
Do you think that online operations are available only on Enterprise Edition? That changed in 12c, there is an operation that is online (without the need for the ONLINE keyword) and available in...
View ArticleClik here to view.
You are in Standard Edition One? Don’t worry.
You want the amazing features of Oracle SQL and PL/SQL with minimal cost. Your database is too large for Oracle XE edition, but not big enough to require the cost of Enterprise Edition. You accept to...
View ArticleDo you use SQL Plan Baselines?
I can hear a lot of complaints about the instability coming from the adaptive features introduced into the optimizer logic at each releases. Giving more intelligence to the optimizer is very good to...
View ArticleClik here to view.
Nothing in feature usage statistics since 12c?
It don’t want to rub salt in the wound about 12c upgrades and Adaptive Dynamic Sampling being overzealous, but here is a case with an unexpected consequence: you see nothing in the ‘Database Feature...
View ArticleQuery V$UNDOSTAT for relevant time window
When you have a query failing in ‘ORA-01555: snapshot too old: rollback segment number … with name … too small’ you have two things to do: Convince the developer that the rollback segment is not too...
View ArticleClik here to view.
Result Cache and 12c ‘fetch first n rows’
At our bi-annual dbiXchange I was talking with Nicolas Jardot about his presentation on Result Cache (don’t forget Jérome witt session about RC at DOAG) where he has shown an unexpected behavior on...
View ArticleClik here to view.
Oracle and Analytic Queries before In-Memory option
Next Tuesday in Geneva I’m presenting Oracle In-Memory Column Store to Business Intelligence people at the Swiss BI Day After defining what is an analytic query, I show the different approaches to...
View ArticleOracle In-Memory Column Store for Business Intelligence at #swissbiday
I’m currently presenting at Swiss BI Day in Geneva about Oracle In-Memory option to improve analytic queries. Here are the slides, uploaded to SlideShare. Oracle in-Memory Column Store for BI from...
View ArticleDbvisit replicate CDC without old values
In a previous post I presented how Dbvisit replicate can capture changes and write them in an audit table with old and new values. Here is how to do it we you want only the new values – with same...
View ArticleIn-memory trickle repopulation
In the ‘traditional’ row store, the indexes are maintained at the same time as rows are changed. It’s different with the In-memory Column Store. Changes are maintained by background processes. When...
View ArticleClik here to view.
Mapping In-memory Column Store to datafile Row Store extents
Oracle In-Memory is an hybrid solution: an In-Memory Column Store in addition to the traditional Row Store. In the IMCS, data is stored in IMCU (In-memory compression units) and metadata is in SMU...
View ArticleClik here to view.
Mapping In-memory CU to values: IMCU pruning
In the previous post we have seen how In-Memory Compression Unit map to the physical persistent storage – table extents. Let’s see now how they are mapped to column values, allowing to optimize the...
View ArticleClik here to view.
11.2.0.4 support? Don’t worry until 2017
Customers reluctant to go to 12c before 12.2, in addition to Standard Edition contract changes when going to 12c, has lead to lot of upgrades to 11.2.0.4 but what about support? Don’t worry. It’s...
View ArticleClik here to view.
You are in Standard Edition, when to worry?
A previous blog post explaining what happens for those in ‘Standard Edition One’ had a “don’t worry” in the title because you can upgrade to SE2 with minimal additional cost – except when you have to...
View ArticleClik here to view.
Oracle Cloud Service – my first outage
We experienced the first planned outage this week-end, so let’s see how it is notified and what happens. EMEA Commercial 2 – Amsterdam Outage notification before: subject: Announcement: Upcoming...
View Article
/fit-in/580x348/filters:format(webp)/english-betterindia/media/media_files/2026/09/17/balaghat-4-2026-09-17-19-01-31.png)
