运行以下代码输出的数据为？（）
import sqlite3
connection=sqlite3.connect("students.db")
cursor=connection.cursor()
cursor.execute("CREATE TABLE students(name TEXT,age INTEGER)")
cursor.execute("INSERT INTO students VALUES('John',19)")
cursor.execute("INSERT INTO students VALUES('John',18)")
cursor.execute("DELETE FROM students WHERE name='John'")
cursor.execute("INSERT INTO students VALUES('John',17)")
cursor.execute("UPDATE students SET age=22 WHERE name='John'")
cursor.execute("SELECT*FROM students")
results=cursor.fetchall()
for row in results:
print(row)
connection.close()
('John',22)
('John',18)
('John',19)
('John',17)