Invalid reference in Oracle database - oracle

Question

I am using Oracle database 19c for a project. I have created the alumni table as shown below:
CREATE TABLE Alumni (
ID NUMBER GENERATED ALWAYS AS IDENTITY ,
First_Name varchar2(20) NOT NULL,
Last_Name varchar2(20) NOT NULL,
Gender char(1) NOT NULL,
CHECK (Gender IN('M','F')),
Graduation_Year number NOT NULL,
check (Graduation_Year>=1980 AND Graduation_Year<=2020),
Degree_Course varchar2(255) not null,
Award_Nominated CHAR(1),
CHECK (Award_Nominated IN('Y','N')),
Award_Won CHAR(1),
CHECK (Award_Won IN('Y','N')),
Phone_Number VARCHAR2(15) not null,
Email_Address VARCHAR2(255) not null,
CONSTRAINT ALUM_PK PRIMARY KEY(ID)
);
Then I tried to define a function that will allow me to search by First or last name in a section of the table, shown below:
CREATE OR REPLACE TYPE alum_row_type is object(ID number,First_name varchar2(20),Last_Name
varchar2(20),Phone_number varchar2(15),Email_Address varchar2(255));
CREATE OR REPLACE TYPE t_alum_row_type as table of alum_row_type;
CREATE OR REPLACE FUNCTION Name_Search RETURN t_alum_row_type
IS
L_alum_row t_alum_row_type := t_alum_row_type();
X integer :=0;
BEGIN
FOR R IN (SELECT ID,First_Name, Last_Name,Phone_Number,Email_Address FROM alumni)
LOOP
L_alum_row.extend;
X:=X+1;
L_alum_row(X):= alum_row_type(X.ID,X.First_Name, X.Last_Name, X.Phone_Number, X.Email_Address);
END LOOP;
RETURN L_alum_row;
END;
After running this, I get this error:
LINE/COL ERROR
--------- -------------------------------------------------------------
10/9 PL/SQL: Statement ignored
10/41 PLS-00487: Invalid reference to variable 'X'
Errors: check compiler log
How can I resolve this issue. I am relatively new to PL\SQL, so please explain it simply.

Answer 1

This is not possible
L_alum_row(X):= alum_row_type(X.ID,X.First_Name, X.Last_Name, X.Phone_Number, X.Email_Address);
You are referencing X.ID, X.Phone_Number etc. . . but declared X as an integer. If you are trying to access the current loop record, try with
L_alum_row(X):= alum_row_type(R.ID,R.First_Name, R.Last_Name, R.Phone_Number, R.Email_Address);
As you declared the loop iterator as R for your cursor
FOR R IN (SELECT ID,First_Name, Last_Name,Phone_Number,Email_Address FROM alumni)

Answer 2

You can eliminate the loop altogether by using BULK COLLECT. Thereby reducing the function to basically a single select statement.
function name_search
return t_alum_row_type
is
l_alum_row t_alum_row_type := t_alum_row_type();
begin
select alum_row_type(id,first_name, last_name,phone_number,email_address)
bulk collect
into l_alum_row
from alumni;
return l_alum_row;
end;