Or, create partial/conditional indexes on the column with appropriate WHERE clause ("...where status = 1", or "where status = 2"...). Optimizer should know which one to use based on your query. Regards, Igor Neyman On Sat, Apr 20, 2013 at 12:19 AM, Mark W. Farnham <mwf@xxxxxxxx> wrote: > I don't see the graph, but I do have a suggestion. > > Now I don't know whether "completed" or "declined" is a more popular value, > but let's say most things end up "completed." > > If your applications can manage interpreting NULL as completed, then you > can > probably permanently and dramatically shrink the size of your index by > using > the value NULL instead of 1 for completed. > > This seems to match your brief description of your use case below. Your > mileage may vary. > > mwf > > -----Original Message----- > From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] > On Behalf Of oracledba > Sent: Friday, April 19, 2013 10:20 PM > To: Oracle-L Freelists > Subject: Index Efficiency > > I have used Jonathan's index efficiency script to plot the graph.The graph > is attached with this mail. > This index is a single column index ( it's like a status column which has > only 4 values say 1 - completed,2- declined,3-suspended,4-unknown).This > table is populated every day and this column's values other than 1 and 2 > are > updated with a new status based on daily's data. > By looking at the graph,what do you infer? How effiecient the index is? > > Thanks > > > > -- > //www.freelists.org/webpage/oracle-l > > > -- > //www.freelists.org/webpage/oracle-l > > > -- //www.freelists.org/webpage/oracle-l