August 2016

Parallel_index hint

Prompted by a recent OTN posting I’ve dug out from my library the following demonstration of an anomalty with the parallel_index() hint. This note is a warning about  how little we understand hints and what they’re supposed to mean, and how we can be caught out by an upgrade. We’ll start with a data set which, to match a comment made in the origina posting rather than being a necessity for the demonstration, has an index that I’ve manipulated to be larger than the underlying table:

After OpenWorld…

Don’t forget that there’s lot of great content still to come your way throughout the rest of the year.

I’ll be part of the OTN Tour in Bangalore, Sydney and Brisbane.

And for a change of pace… I’ll be doing a keynote  at UKOUG !  (I’m the person in the list below who isn’t a senior director or vice president Smile)

Hope to see you at some or all of these events.

 

Resizing ASM Disks On Modern Systems. Real Application Clusters Doesn’t Make It Any More Difficult. An XtremIO Example With RAC.

My recent post about adding space to ASM disk groups by resizing them larger, as opposed to adding more disks, did not show a Real Application Clusters example. Readers’ comments suggested there is concern amongst DBAs that resizing disks (larger) in a RAC environment might somehow be more difficult than in non-RAC environments. This blog entry shows that, no, it is not more difficult. If anything is true it is that adding disks to ASM disk groups is, in fact, difficult and invasive and that resizing disks–whether clustered systems or not–is very simple. The entire point of this short blog series is to endear DBAs to the modern way of doing things.

Started at Amazon! … want to join me?

(Disclamer: any opinions expressed here are fully my own and not representative of my employer)

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photo by alvaroprieto  (cc 2.0)

Oracle Database Cloud (DBaaS) Performance Consistency - Part 3

#333333; font-family: "verdana" , "arial" , sans-serif; font-size: 13px; line-height: 16.9px;">This is the third part of this installment, comparing the performance consistency of the DBaaS cloud offering with a dedicated physical host.

How important is "up to date" to you ?

I wrote a post a while back showing how one of the options with an Oracle Text index is to keep that index perfectly updated with its underlying table.  (Long termers with Oracle may know that this is a relatively recent addition to Text indexes, which historically were updated with calls to CTXSYS.CTX_DDL.SYNC_INDEX, either on demand or via the scheduler).

I also said that there is “no such thing as a free lunch”, as refreshing that index for every single commit introduces overheads.  So let’s explore that a little more thoroughly

Copy Data Management with Delphix on Exadata

I’ve been busy reading and testing everything I can with Delphix, whenever I get a chance.  I’m incredibly fascinated by copy data management and the idea of doing this with Exadata is nothing new, as Oracle has it’s own version with sparse copy.

Oaktable World 2016 Sept 19 & 20 is on !!

Having take a new job at Amazon just two weeks ago and moving to Seattle (!)  I didn’t have the time nor was it practical to set up Oaktable World  this year. Luckily Kellyn Pot’vin has taken over the mantel !

Get the info straight from the horses mouth at her blog.

The following content has been graciously supplied from Kellyn’s blog:

Oak Table World is FREE to the PUBLIC!  We don’t require an Oracle Open World badge to attend, so bring a friend and they’ll owe you big time!

otwHere is the current schedule:

Oaktable World 2016 Oct 19 & 20 is on !!

Having take a new job at Amazon just two weeks ago and moving to Seattle (!)  I didn’t have the time nor was it practical to set up Oaktable World  this year. Luckily Kelly Pot’vin has taken over the mantel !

Get the info straight from the horses mouth at her blog.

The following content has been graciously supplied from Kellyn’s blog:

Oak Table World is FREE to the PUBLIC!  We don’t require an Oracle Open World badge to attend, so bring a friend and they’ll owe you big time!

otwHere is the current schedule:

Little things worth knowing: using Remote Diagnostic Agent more effectively with profiles

RDA, or the Remote Diagnostics Agent, has been around for a little while. Over the time, and with the growing number of Oracle’s acquisitions it has become, shall we say, a little more difficult to handle. It appears to me as if every one of them will have its diagnostics handled by RDA making it hard to focus on something specific, like for example the database.

I won’t go into very detail of the Remote Diagnostic Agent in this post; please make sure you read and understand the documentation on MOS and the README* files that come with it before using it.

I based this blog post on Oracle Linux 7.2 and RDA 8.12.16.6.14 in case you find this via a search engine.

Basic Usage