Hello Dennis SAS has progressed a little in the last years and now offer a complete DW solution, including ETL tools.
You can use their tools also to populate and query oracle. Yechiel Adar Mehish ----- Original Message ----- To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]> Sent: Saturday, May 04, 2002 2:48 AM > Rachel - I always find it helpful to understand something if I know the > origins. I worked with SAS several years ago. At that time it was a > statistical analysis package. A scientist or engineer could load a set of > test data into it and perform various arithmetic and statistical analyses. > Today most of that can be done with Oracle or MS Excel. My point is that I > would expect it to be heavily biased toward mathematical capabilities. Like > Data Mining, which is all statistics. Learn what that term means. > To learn Data Warehousing, I would encourage you to just do some > "Googling" and find good tutorials. An excellent newslist is dwlist. > Instructions: > > For help with list commands, send a message > to <mailto:[EMAIL PROTECTED]> with the > word "help" in the body of the message. > > The magazine http://www.intelligententerprise.com/ has some excellent > information. I would search for "Ralph Kimball". He is one of the leading > figures in the DW arena. Look for some of his earliest columns on the > magazine site. He also answers questions on dwlist from time to time. > > The main change you need yourself is to forget normalization. DBAs that > can't get past that point don't last long in the DW field. In the early days > the DW people would patiently explain the reasons to a DBA, but today there > are enough DBAs that have made the leap that a hard-headed normalization > bigot just isn't tolerated. It is much easier to just ask for a replacement > DBA. > The reason normalization isn't adhered to in DW is that users will > be creating their own queries and they can't understand 10-table joins with > outer joins, etc. A DW is usually loaded and then queried. Our DW is loaded > each weekend and then queried all week. So a DW is deliberately denormalized > and contains redundant data for ease of use. > OLTP databases have no concept of "time". A DW is all about time. To > reconstruct what the situation is at various points of time, the DW has > loads of historical data. For example, marketing people need to be able to > reconstruct the amount of business they did with a customer over a period of > time last year and compare it with the same period this year. > So between denormalization and tons of detailed historical data, DWs > are normally BIG! Fortunately they are usually read-only. > For Oracle, you want Enterprise Edition with the partitioning > option. And study Oracle Materialized Views. > In schema, a DW is usually a central fact table and 4-6 dimension > tables. Less than 4 dimensions and you don't need a DW. More than 6 and > marketing people can't understand the model. Normally the fact table is much > larger than the others, but not always. One of Wal-Mart's dimension tables > is each person in the U.S. Just size each of those tables, and you've got > your size. Growth is easy to predict. Ralph Kimball warns that often people > will get the grain wrong. They will size it for data summarized at the > weekly level, then after it is built they will realize that isn't going to > cut it and need a daily level. You must start almost from scratch and get 7 > times the disk capacity. That is the fun side of being a DW DBA. Your > cynical instincts will still serve you well, just get them away from > normalization and worry about getting the grain right. > Okay, I've rambled along here too long. Hope that gets you off on > the right foot. > > -----Original Message----- > [mailto:[EMAIL PROTECTED]] > Sent: Friday, May 03, 2002 5:08 PM > To: Multiple recipients of list ORACLE-L > > > > > Okay, my background is OLTP, but we are looking at a data warehousing > project > here.... > > any and all help appreciated! Specifically: > > 1) does anyone have any experience with a product called "SAS > Datawarehousing > Administrator" (or SAS)? > 2) how do I go about doing rough estimates of sizing needs, assuming I will > get > rough numbers of information being collected, growth rates, length of > history to > keep, etc. > > help? > > Rachel > > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: > INET: [EMAIL PROTECTED] > > Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 > San Diego, California -- Public Internet access / Mailing Lists > -------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: DENNIS WILLIAMS > INET: [EMAIL PROTECTED] > > Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 > San Diego, California -- Public Internet access / Mailing Lists > -------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Yechiel Adar INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
