Solve the following questions using Oracle

_Use an outer join to find names of theinstructors who never taught any course.

The Data:

create table classroom

    (building       varchar(15),

    room_number        varchar(7),

    capacity       numeric(4,0),

     primary key (building, room_number)

    );

create table department

    (dept_name      varchar(20),

    building       varchar(15),

     budget     numeric(12,2) check (budget > 0),

     primary key (dept_name)

    );

create table course

    (course_id      varchar(8),

    title          varchar(50),

    dept_name      varchar(20),

    credits        numeric(2,0)check (credits > 0),

     primary key (course_id),

     foreign key (dept_name) referencesdepartment

        on delete setnull

    );

create table instructor

    (ID         varchar(5),

    name           varchar(20)not null,

    dept_name      varchar(20),

    salary         numeric(8,2)check (salary > 29000),

     primary key (ID),

     foreign key (dept_name) referencesdepartment

        on delete setnull

    );

create table section

    (course_id      varchar(8),

sec_id         varchar(8),

    semester       varchar(6)

        check (semesterin (‘Fall’, ‘Winter’, ‘Spring’, ‘Summer’)),

    year           numeric(4,0)check (year > 1701 and year < 2100),

    building       varchar(15),

    room_number        varchar(7),

    time_slot_id       varchar(4),

     primary key (course_id, sec_id,semester, year),

     foreign key (course_id) referencescourse

        on deletecascade,

     foreign key (building, room_number)references classroom

        on delete setnull

    );

create table teaches

    (ID         varchar(5),

    course_id      varchar(8),

    sec_id         varchar(8),

    semester       varchar(6),

    year           numeric(4,0),

     primary key (ID, course_id, sec_id,semester, year),

     foreign key (course_id,sec_id,semester, year) references section

        on deletecascade,

     foreign key (ID) referencesinstructor

        on deletecascade

    );

create table student

    (ID         varchar(5),

    name           varchar(20)not null,

    dept_name      varchar(20),

    tot_cred       numeric(3,0)check (tot_cred >= 0),

     primary key (ID),

     foreign key (dept_name) referencesdepartment

        on delete setnull

    );

create table takes

    (ID         varchar(5),

    course_id      varchar(8),

    sec_id         varchar(8),

    semester       varchar(6),

    year           numeric(4,0),

    grade       varchar(2),

     primary key (ID, course_id, sec_id,semester, year),

     foreign key (course_id,sec_id,semester, year) references section

        on deletecascade,

     foreign key (ID) references student

        on deletecascade

    );

create table advisor

    (s_ID           varchar(5),

    i_ID           varchar(5),

     primary key (s_ID),

     foreign key (i_ID) referencesinstructor (ID)

        on delete setnull,

     foreign key (s_ID) references student(ID)

        on deletecascade

    );

create table time_slot

    (time_slot_id       varchar(4),

    day            varchar(1),

    start_hr       numeric(2) check(start_hr >= 0 and start_hr < 24),

    start_min      numeric(2) check(start_min >= 0 and start_min < 60),

    end_hr         numeric(2)check (end_hr >= 0 and end_hr < 24),

    end_min        numeric(2)check (end_min >= 0 and end_min < 60),

     primary key (time_slot_id, day,start_hr, start_min)

    );

create table prereq

    (course_id      varchar(8),

    prereq_id      varchar(8),

     primary key (course_id, prereq_id),

     foreign key (course_id) referencescourse

        on deletecascade,

     foreign key (prereq_id) referencescourse

    );