Blog Roll

You may have noticed that the blogroll in the right-hand panel has recently become a lot shorter. As I pointed out a couple of weeks ago, the Oak Table Network has a new website (which is in my blogroll) that includes an aggregator for all the Oak Table members so I’ve started removing individual Oakies [...]


There was a news item in the UK last week about a man in Chideock, Dorset who staged a protest about the volume of heavy traffic that has to come through the village where he lives. A pedestrian crossing has recently been installed on the road, using traffic-light control. So one morning he decided to [...]


I’ve just received an email telling me that I’m a linchpin – according to this picture on Seth Godin’s website. Filed under: Uncategorized

Quiz Night

I have two queries designed to return the same result set in the same order. In outline they look like this (look carefully at the from clauses): select ... from tableA t1, tableB t2 where t1.filter = ... and t2.join = t1.join and t2.filter = ... order by ... select ... from tableA t1, tableB [...]

A blog to watch

I see that Nigel Noble has started blogging. I’ve spent some time at the company where he works, so I know how close he gets to the bleeding edge of Oracle technology – you might want to keep an eye on what he has to say. I’ve added his URL to the list of links [...]

Refreshing a Test Database using exp/imp

I’ve just taken a quick look at the Calendar and it appears to be 2010. However I’m still seeing, and being asked, to refresh a number of test databases using schema mode exports. This can present a challenge because there are a number of database objects that typically aren’t created by a schema mode import. [...]

Advert – USA

Last chance to book: I’ll be speaking in Boston, New York, and Cleveland the week after next. Dates and topics: Boston: 17th – Writing Optimal SQL Boston: 18th – Troubleshooting and Tuning New York: 19th May – Writing Optimal SQL Cleveland: 20th May – All about Execution Plans New York is fully booked with a waiting [...]

Temporary note

I’ve just added a link to Graham Wood’s presentation about ASH (v$active_session_history) to my catalogue of Statspack Examples. I’ve also added a link to the “Partition Stats” catalogue pointing to Doug Burn’s latest blog; I’ve also added a permanent entry for partitions to the “Special Links” menu on the right. This note will be deleted [...]

DW Introduction

Greg Rahn has been writing a short series on “Core Performance Fundamentals of Oracle Data Warehousing”. Here’s his catalogue of the first four or five articles in the series.

New Features, New Defaults, New Side-Effects

11.2 provides a new feature, deferred segment creation, which is the default for Enterprise Edition databases, whilst this feature is rather nice in some restricted circumstances, there are a couple of side effects which may catch the unwary and in some cases make previously valid operations significantly more difficult.