For good performance in oracle need tunning your database. Can use Gather your schema database for the example :

Gather Schema :

BEGIN
  SYS.DBMS_STATS.GATHER_SCHEMA_STATS (
     OwnName           => 'DIARYCODING_DB'
    ,Granularity       => 'DEFAULT'
    ,Options           => 'GATHER'
    ,Gather_Temp       => FALSE
    ,Estimate_Percent  => 0
    ,Degree            => 4
    ,Cascade           => FALSE
    ,No_Invalidate     => FALSE);
END;

www.diarycoding.com