Gogala, so , if there is an index on a column like SEX , then it means data ( in that index ) is skewed. am i right ?
for an index , if cardinality is low OR clustering_factor is high --> it means data is skewed. sorry if i sound stupid :-| Is "SKEW" used with respect to index or table or both ? >>..data is the index is not distributed evenly i cannot understand this. index data is not disturbed evenly with respect to **** ? can u explain ( if possible ) with an example plz ? Mladen Gogala <[EMAIL PROTECTED]>: > It's actually a substitute for another word which is not to be repeated on > this list because of the presence of the ladies, much like "heck", "darn" > or > "frigging". It means that the data in the index (you found that word in the > chapter about indexes, statistics and the Curses Based Optimizer, am I > right) > is not distributed evenly, with small variations in the number of rows for > any > given key, but that there is a small subset of keys which corresponds to > significant part of the table. Speaking mathematically, there exists at > least > one value in the indexed columns so that the number of rows corresponding > to > this value is significantly larger then the average number of rows per > value. > In other words, it means that the application relying on such index is > skewed up. -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: orababy INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- 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).
