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Hi,
I need some advice/opinions from someone experienced with large scale data warehousing.
I'm working on a fairly large data warehouse (around 3 TB), and we're using Oracle 10.1.0.2.0.
So, I found out about MV's and Star Transformations, and that we're not
using them.
Naturally I decided to try them out in our test environment and I was
more than pleased (actually, I nearly wet my pants) with the potential
performance boost we could get for some of our more critical solutions.
However, I also noticed that the production environment has the following settings:
star_transformation_enabled = false
query_rewrite_integrity = enforced
...which basically disables all the cool stuff. In the testing environment I used the following:
star_transformation_enabled = true
query_rewrite_integrity = trusted (to make use of func. dep in
dimensions)
I would like to stand on somewhat solid grounds and increase my understanding before aproaching our DBA's with the suggestion to change system global settings :)
Basically, my question(s) are:
I would be happy to know what you think about this. Any thoughts, opinions are welcome since this is new grounds for me.
Best Regards
R.
Received on Mon Nov 27 2006 - 05:19:06 CST