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Me and my Exadata Xmas present

Actually it is a cardboard cutout – not me, the server. We have real ones downstairs in the data centre but my cardboard one doesn’t cost as much to support or keep air-conditioned.

Merry Xmas to all


UKOUG 2012 – Day 3

Today was Unconference day at UKOUG which was a pot-pourri of talks all lasting about 20 minutes each. The talks were interesting although sparsely attended, which was actually a benefit as there was plenty of opportunity for interaction and indeed complete disregard of the main topic under discussion.

I didn’t actually get to see any scheduled presentations but I had seen enough in the previous two days to keep me going for a while.

So adios UKOUG at Birmingham and welcome to the Tech conference in Manchester next December.

UKOUG 2012 – Day 2

A deep dive into Dataguard is a tough way to start the day off but Emre Baransel handled it well. I jotted down about 6 or 7 takeaways for later investigation. Much of the talk was about tuning the redo log apply and I must admit that I don’t consider we have many problems in that area across the estate but it is still worth reviewing. One topic that stuck me as looking at in more detail was the ability to recover a standby database from a primary backup. Chatting to a few people afterwards they had all heard of the capability to do that but had never tested it.

UKOUG 2013 – Day One

The UKOUG conference comes around again and the first two presentations re-confirmed why I attend. Jonathan Lewis was talking about generating data for test cases and I realised that I could generate the data for an interesting issue at work involving the non use of an index and a histogram with a bucket size of 60. It wasn’t so much that the data was hard to create it was that it had just not occurred to me to do so.

Managing OCR and voting disks

This is basically a set of notes I wrote for myself about adding new voting disks and OCR disks to a sandpit RAC cluster as part of testing for migration between HP XP disk array and HP 3PAR disk array. The o/s was HPUX with database.

What is the ‘Unconference’?

It’s that time of the year again and UKOUG 2012 beckons. The full schedule of talks can be seen at If going it is a help to the organisers to select  your itinerary in advance as then each session can be scheduled to be in a hall that can accommodate all the attendees who have expressed interest and nobody is disappointed.

Using Datapump from SQLDeveloper

One problem that we all have is with exporting/importing between different versions of the datapump client. The following error is not uncommon

UDI-00018: Data Pump client is incompatible with database version

Permissions problem with and tnsnames.ora

There is a Bug documented in MoS regarding the setting of permissions by the script (which calls  This causes the ownership of grid home to be owned by root and permissions given to oinstall group

app/gridsoft/ $ls -ld

drwxr-x---  65 root       oinstall      2048 Feb 27  2012 . 

Balancing ASM disks in one command – the benefits

As a response to my previous post about adding and dropping ASM disks with one command Emre Baransel asked a question as to whether it was more efficient or not to do it as one or two commands. It was easier to add  a second post complete with screen shots rather than just a simple reply.

My test system was a 3.5Tb database spread across 10 512Gb luns.

The first choice was to add and drop in one command

ASM – Adding and dropping disks in one command

One of the possibilities within ASM that is not widely documented is the opportunity to add disks, drop disks and set the rebalance power all in one command.

One might wonder when you might be both adding and dropping disks simultaneously from the same disk group. Recently we have been migrating to a new storage array and this command comes in very useful in that situation

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