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;
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