enrolled in a yearly course has incorrect --data in records with ids between 20 and 100 (inclusive)

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--A table containing the students enrolled in a yearly course has incorrect 
--data in records with ids between 20 and 100 (inclusive).
DROP TABLE IF EXISTS enrollments;
CREATE TABLE enrollments
  (id int NOT NULL PRIMARY KEY,
  year int NOT NULL,
  studentId int NOT NULL)
  -- insert sample data
Declare @Id int
Set @Id = 1

Declare @studentId int
Set @studentId = 10

Declare @LowerLimitForYear int
Declare @UprerLimitForYear int

Set @LowerLimitForYear= 2000
Set @UprerLimitForYear= 2100

Declare @RandomYear int
while(@Id <= 200)
Begin
	select @RandomYear =  ROUND((@UprerLimitForYear -@LowerLimitForYear)* RAND() +1,0)*100
	Insert into enrollments
		Values(@Id,@RandomYear,@studentId)
	Set @Id = @Id +1
	Set @studentId = @studentId +10
		
END

--Write a query that updates the field 'year' 
-- of every faulty record to 2015.
update enrollments
set [year] = 2015
where id between 20 and 100