Data Warehousing
pineryjim@aol.com (PINERYJIM) writes: > >definition. Just what is it you do when you warehouse data? Or, from a > >different perspective, what kind of data does a warehouse contain? Or, am > >I missing the point altogether? parmentr@oasis.cc.purdue.edu (W J Parmenter) replies: > Warehouse tables typically have lots of indexes and may be tuned to > accommodate the most frequent sorts of queries. Some folks even > recommend (horrors!) de-normalizing tables to the extent of, at > least, pre-joining lookup tables to create faster access at the > (to end-users) negligible cost of redundant data(!) in the warehouse. I am just making this up, but that's the definition I use. > The really *new* thing is that warehoused data is intended to be > accessed by end-users so they can get the data themselves and use > desktop tools to turn the data into the information they need. Exactly. The ODBC tools that have come out in the past year or so make this kind of thing possible. While people have been raving about PC end-user empowerment for a long time, this is the first time I've seen anything that would really work for databases. I have submitted a paper (which is under review) for the Informix World-Wide conference titled "Database Design for the ODBC Data Warehouse". The premise is very simple: that users now have access to the *data structures* and that column names should be made with the users in mind. That's a big change from the days when all that was hidden behind a big 4gl application. De-normalizing, pre-joining, and thorough indexing tailored to queries is another aspect of db design that has changed, and that I (maybe others, too?) am calling "data warehousing". As always in this rapidly evolving business, that which survives to wear the name does not always match the definition at the inception. Data Warehousing will be around for a while, and probably not only as we see it today. __________________________________________________________________ | Clem Akins Standard Disclaimers Apply | |Reynolds Metals Co, Alloys Plant "Climb High, Cave Deep!" | | Muscle Shoals, Alabama USA cwakins@leia.alloys.rmc.com | |________________________________________________________________|