Assigning more than one column to a collection using BULK COLLECT - oracle

Question

I am not sure why I am getting this error with this code, Please help me with debugging this code Thanks in advance.
declare
type emp_t is table of employees%rowtype
index by pls_integer;
rec emp_t;
begin
select employee_id,salary,manager_id bulk collect into rec
from employees where rownum <100;
forall i in 1..rec.last
update employees
set salary=salary+10
where employee_id=rec(i).employee_id;
end;
ORA-06550: line 7, column 3:
PL/SQL: ORA-00913: too many values
ORA-06550: line 6, column 3:
PL/SQL: SQL Statement ignored
06550. 00000 - "line %s, column %s:\n%s"
*Cause: Usually a PL/SQL compilation error.
*Action:
I have changed the code to the below format but it's still giving me "expression is of wrong type error"
declare
type emp_t is table of employees%rowtype
index by pls_integer;
rec emp_t;
begin
for val in (
select employee_id,salary,manager_id
from employees where rownum <100)
loop
rec:=val;
end loop;
forall i in 1..rec.last
update employees
set salary=salary+10
where employee_id=rec(i).employee_id;
end;

Answer 1

Use either one or the other:
TYPE emp_t IS TABLE OF employees%ROWTYPE INDEX BY PLS_INTEGER;
-- ^^^^^^^^^^^^^^^^^
-- each record is "one row" of table `employees`
...
SELECT * BULK COLLECT INTO rec FROM employees WHERE ROWNUM < 100;
-- ^
-- get all columns for each row
Or
TYPE emp_rec IS RECORD (
employee_id employees.employee_id%TYPE,
salary employees.salary%TYPE,
manager_id employees.manager_id%TYPE
);
TYPE emp_t IS TABLE OF emp_rec
-- ^^^^^^^
-- each record only contains the necessary fields
...
SELECT employee_id,salary,manager_id BULK COLLECT INTO rec FROM employees WHERE ROWNUM < 100;
-- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-- get only what we need (and in that particular order)
Very probably you are looking for the second form. Using a custom type for the RECORD you are trying to bulk collect. Please notice the use of %TYPE attribute in the record declaration. That's an alias to the type of each column.

Answer 2

emp_t is declared as ROWTYPE, that includes all the columns,
but while retrieving records your are retrieving only employee_id,salary,manager_id,
that could be the reason of your error.
Try this :
declare
type emp_t is table of employees%rowtype
index by pls_integer;
rec emp_t;
begin
select employee_id,salary,manager_id bulk collect into rec
from employees where rownum <100;
forall i in 1..rec.last
update employees
set salary=salary+10
where employee_id=rec(i).employee_id;
end;
The second one seem to have other issues like TYPE difference VAR and REC