Path: news.easynews.com!easynews!news-out.cwix.com!newsfeed.cwix.com!news.tele.dk!small.news.tele.dk!130.133.1.3!fu-berlin.de!uni-berlin.de!61-217-217-148.hinet-ip.hinet.NET!not-for-mail From: Dino Hsu Newsgroups: comp.databases.oracle.server Subject: Star Transformation Date: Wed, 10 Oct 2001 23:30:39 +0800 Lines: 21 Message-ID: NNTP-Posting-Host: 61-217-217-148.hinet-ip.hinet.net (61.217.217.148) Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: fu-berlin.de 1002727807 22605616 61.217.217.148 (16 [41926]) X-Newsreader: Forte Agent 1.8/32.548 Xref: easynews comp.databases.oracle.server:120828 X-Received-Date: Wed, 10 Oct 2001 08:44:19 MST (news.easynews.com) Dear all, I've just read Chapter 16 Schmeas, Oracle8i Data warehousing Guide Release 2 (8.1.6), I found star transformation to be very interesting. I want to confirm my understanding about how star transformation works: 1.The initialization parameter STAR_TRANSFORMATION_ENABLED set to true. 2.Bitmap indexes created for all foreign keys of the fact table. 3.Bitmap indexes created for primary keys of the fact table and for large dimension tables. (full table scan is fine for small dimension tables) 4.Remote small dimension tables are allowed, but not the fact table.(not sure) 5.Star transformation is general enough to include both star schema and snowflake schema. In my idea, star schema is a special case of the more general snowflake schema. Thanks, Dino