star_transformation_enabled = true

Can someone explain what this does in the pfile?

star_transformation_enabled = true

it tells Oracle you are using a star schema design (data warehouse) and it will allow oracle to rewrite your query (during parsing?) to utilize the star schema architecture.

I don't know how much it helps, but I couldn't see NOT using it.

look at the docs for Datawarehousing. It's pretty self explained.

Here is the doc that could help you to undestand the star schema.

http://www.oradoc.com/ora816/server....ical.htm#97642

Good luck,
Sam

However - this only has benefit when dealing with an actual star schema. Oracle support just had us turn the option off (disclaimer: It was not I that turned it on :D - we are OLTP) - they suspect that it might be the cause of some problems. I am told there have been issues related to that option.

- Chris