Adding to David, internally it will create function based index, basically we are making sure all rows(rowid) is there in index On Fri, Mar 29, 2013 at 5:26 PM, David Fitzjarrell <oratune@xxxxxxxxx>wrote: > Yes, it applies to 11g. The addition of the 1 in the column list ensures > that NULL values for the key column will be indexed. Normally a b-tree > index will not contain entirely NULL keys so this is a way to 'fix' that. > I blogged on this sometime back: > > http://dfitzjarrell.wordpress.com/2008/04/09/a-tale-of-two-indexes/ > David Fitzjarrell > > > > ________________________________ > From: Eriovaldo Andrietta <ecandrietta@xxxxxxxxx> > To: ORACLE-L <oracle-l@xxxxxxxxxxxxx> > Sent: Friday, March 29, 2013 4:05 PM > Subject: What does it mean when CREATE INDEX > > Hi Friends, > I saw a command like this: > > CREATE INDEX emp_ename ON emp(ename desc, 1); > > The benefit pointed of this solution is that when we use in the where > clause > > --> where name IS NULL > > sometimes the optimizer does not use the index. > > In the test that person did, using ... emp(name,desc,1) the optimizer > used the index. > > Does it apply to Oracle 11g ? > > Did anybody have any experience using this resource ? > > I will test it too. > > Regards > Eriovaldo > > > -- > //www.freelists.org/webpage/oracle-l > -- > //www.freelists.org/webpage/oracle-l > > > -- Thanks & Regards, Taral Desai -- //www.freelists.org/webpage/oracle-l