index

hello group this is my select : distretto and numero is not primary key select * from tt_master where distretto=0444 and numero=00563921 ---------------------------------------------------------------------------- -------------------i have created the this index : CREATE index ttmaster3 ON tt_master ( distretto,numero ) in dbdati3 result: index name Owner Type Cluster Columns ttmaster3 olbb dupls No distretto numero ---------------------------------------------------------------------------- -- when i do the explain plain result this is: QUERY: ------ select * from tt_master where distretto=0444 and numero=00563921 Estimated Cost: 36484 Estimated # of Rows Returned: 1 1) olbb.tt_master: SEQUENTIAL SCAN Filters: (olbb.tt_master.distretto = 444 AND olbb.tt_master.numero = 563921 ) why ????? tanks

Did you run "update statistics for table tt_master" ? "DBA-BABY" <pippo99@libero.it> a 'crit dans le message de news:rdpza.25930$Ny5.775967@twister2.libero.it... > > hello group > > this is my select : > distretto and numero is not primary key > > select * from tt_master where distretto=0444 and numero=00563921 > -------------------------------------------------------------------------- -- > -------------------> i have created the this index : > > CREATE index ttmaster3 ON tt_master > ( > distretto,> numero > ) > in dbdati3 > > result: > > index name Owner Type Cluster Columns > > ttmaster3 olbb dupls No distretto > numero > > -------------------------------------------------------------------------- -- > -- > when i do the explain plain result this is: > > QUERY: > ------ > select * from tt_master where distretto=0444 and numero=00563921> > Estimated Cost: 36484 > Estimated # of Rows Returned: 1 > > 1) olbb.tt_master: SEQUENTIAL SCAN > > Filters: (olbb.tt_master.distretto = 444 AND olbb.tt_master.numero = 563921 > ) > > > why ????? > > > tanks > > > > >

On Fri, 23 May 2003 13:19:19 GMT, "DBA-BABY" <pippo99@libero.it> wrote: Need to run the required 'update statistics'. > >hello group > >this is my select : >distretto and numero is not primary key > >select * from tt_master where distretto=0444 and numero=00563921 >---------------------------------------------------------------------------- >------------------->i have created the this index : > >CREATE index ttmaster3 ON tt_master >( >distretto,>numero >) >in dbdati3 > >result: > >index name Owner Type Cluster Columns > >ttmaster3 olbb dupls No distretto > numero > >----------------------------------------------------------------------------