执行以下代码，数据表中共有几条数据？（ ）

import sqlite3

conn = sqlite3.connect('student_info.db')

cursor = conn.cursor()

cursor.execute('''CREATE TABLE IF NOT EXISTS Student

(id INTEGER PRIMARY KEY, name TEXT, age INTEGER)''')

cursor.execute("INSERT INTO Student (id, name, age) VALUES (1, 'Alice', 20)")

cursor.execute("INSERT INTO Student (id, name, age) VALUES (2, 'Bob', 2)")

cursor.execute("INSERT INTO Student (id, name, age) VALUES (3, 'Charlie', 21)")

cursor.execute("SELECT * FROM Student")

students = cursor.fetchall()

for student in students:
print(f"ID: {student[0]}, Name: {student[1]}, Age: {student[2]}")

cursor.execute("UPDATE Student SET age = 23 WHERE id = 2")

cursor.execute("DELETE FROM Student WHERE id = 3")

conn.commit()

conn.close()