Applying the formulas as documented in Oracle 8, and comparing the results to an actual Oracle 8i database (a data warehouse; I'm interested only in 8 fact tables ranging in size from 10 million to 500 million rows; the 9i database is for a new client, and is the reason for this exercise) yields the following: - Table estimates for non-partitioned tables are within 10% (uniformly lower for the estimate than the actual) of the actual - But the table estimates don't take into account partitioned tables, which are farther off - B-Tree index estimates were modified to reflect the changed size of the ROWID; most are still within 10% deviation from the actual - We're still looking at the bitmap indexes (determining cardinality) and the local partitioned indexes More problematic is actually determining how many rows are going to be in each fact table -- both at startup and at 6 month intervals. Unfortunately, we're not going to 10g any time soon, so I can't use the EM facility Lex mentioned. Leslie -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx]On Behalf Of Pete Sharman Sent: Tuesday, June 15, 2004 1:42 PM To: oracle-l@xxxxxxxxxxxxx Cc: Peter Ross Sharman Subject: RE: Lost appendix: Space Estimations for Schema Objects Leslie It was taken out because there are so many variations and permutations possible that a generic formula is never going to be realistic. The only realistic way to get space estimations is to load a "typical" set of data (whatever that is) and then extrapolate to Production sizes, based on history and so on. Pete "Controlling developers is like herding cats." Kevin Loney, Oracle DBA Handbook "Oh no, it's not. It's much harder than that!" Bruce Pihlamae, long-term Oracle DBA -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Leslie Tierstein Sent: Wednesday, 16 June 2004 3:02 AM To: oracle-l Subject: Lost appendix: Space Estimations for Schema Objects The Oracle 8.0 documentation had an Appendix A to the "Oracle Server Administrator's Guide" on "Space Estimations for Schema Objects". It gave formulas for approximating the amount of disk space that would be taken up by tables and indexes, taking into account block size, init trans, pct free, etc. The appendix seems to have vanished in the 9i documentation -- at least I can't find it. Does anyone know if/where this information still exists, either in the Oracle documentation set or some other documentation? Thanks, Leslie Leslie Tierstein Senior Consultant Vision Chain, Inc. The first software to power the demand data network phone: 202-261-3549 ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------