Question Time

Friday, February 17th, 2006 by Mark Rittman

I’ve had a few questions through recently, and rather than answer
them directly via email, I thought I’d publish them here. Going into
the future, I’ll only be answering questions that get posted to the
forum (http://www.rittman.net/forum),
as it makes the answers available to everyone and other people can
step in and answer if I’m not available. Anyway, here goes…
“I […]

What’s that about then?

Thursday, February 16th, 2006 by Peter Scott

At the risk of Tom Kyte telling me that I have given up thinking…
Any ideas why this appeared as part of a WHERE predicate (or more to the point why write it!)

AND
( case
when T.V_STATUS = ‘A’ then ‘Active’
when T.V_STATUS = ‘D’ then ‘Delisted’
else ‘Unknown Status’
end
) = ‘Active’ )

I might have said … AND T.V_STATUS […]

Real-life parallels

Wednesday, February 15th, 2006 by Peter Scott

If you read AskTom you will probably know that there is no such thing as a universal go-faster switch in Oracle. Everything is “maybe faster, maybe slower and your mileage may vary”.
Over the past week or so we have been user-testing a revised parallelism setting on a 3 TB DW system. Originally, all of the […]

Collecting statistics

Wednesday, February 15th, 2006 by Peter Scott

For a while we have used DBMS_STATS.GATHER_SCHEMA_STATS with the gather stale option to collect statistics on one of our Oracle 9.2 data warehouses. It was perhaps a little slower than our old approach but it did the job and was also code not written (and hence not maintained) by us; from posts past you know […]

Updates to Recent Articles

Wednesday, February 15th, 2006 by Mark Rittman

Just a couple of updates. If you found the article last week on Oracle OLAP
memory management useful, Chris Chiappa sent an email through to me this evening
with some clarifications and corrections. I’ve annotated the article with Chris’
comments and you can

read the updated version here. Thanks very much Chris, much appreciated.
If you’ve been following the postings […]

Using Oracle Business Rules as an ETL Front-End

Saturday, February 11th, 2006 by Mark Rittman

I went to see a new customer last week who was looking to put together a
company MIS system. The system needed to load and transform some data prior to
analyzing it using OracleBI Discoverer, and to do the transformation they were
looking at using OracleBI Warehouse Builder, and a new Oracle product called
Oracle Business Rules. Oracle Business […]

Some days the developer in me emerges and then off I go

Thursday, February 9th, 2006 by Peter Scott

A couple of days ago I downloaded the new release of JDeveloper. Although I had been playing with the Early Adopter version for some while I wanted to see how the official release looked. I had already recommended it to my Java developers and wanted to make sure my opinion still stood. It did; even […]

Some days the developer in me emerges and then off I go

Thursday, February 9th, 2006 by Peter Scott

Due to a dropped internet connection this entry was duplicated to here So this one is edited to history, and the more recent one stands. If only because Niall added a comment on the content and Bob and I did not.

Understanding Oracle OLAP Memory Management

Wednesday, February 8th, 2006 by Mark Rittman

When you work with the OLAP functionality in Oracle Database 10g, you need to be aware of how it handles memory. Just like a relational data warehouse, data held in multidimensional datatypes makes use of memory structures such as the System Global Area (SGA), Program Global Area (PGA) and User Global […]

Understanding Oracle OLAP Memory Management

Wednesday, February 8th, 2006 by Mark Rittman

When you work with the OLAP functionality in Oracle Database 10g, you need to
be aware of how it handles memory. Just like a relational data warehouse, data
held in multidimensional datatypes makes use of memory structures such as the

System Global Area (SGA),

Program Global Area (PGA) and User Global Area (UGA); in addition, the OLAP
Option uses a […]