Value ordered NUSI - response (1) by rajeev saravanan

Hi,
NUSI is always an all amp operation but not a full table scan.
So it will first ask the subtables on all the amps and querying this subtable based on a non eqality condition
as it is in the case above will be fatser when the rows in the sub table are value orderd (date column above) rather than
hash order as in case of normal NUSI
So the advantage lies in how quick it can get the info from the sub tables.
if your where clause is based on a equilty condition then hash orderd NUSI will be fatser however if its based on a range
then value ordered NUSI will be faster as it need not scan the entire subtable.
 
Regards
R.Rajeev