Giving permission for each table within a database I want to give different permission for different tables within a single database for a user.For example a user has full permission to a table while for another table only read permission.How it can be done within a database?
In Oracle (and, realistically, most any reasonable database), everything is denied other than what is granted.  So simply grant the user the privileges you want him to have

GRANT select, update, delete
   ON table_owner.table_name
   TO username;

GRANT select
   ON table_owner.another_table_name
   TO username;