flask 读取mysql 表_flask 项目，想获取数据库中的某个表有多少条数据记录该如何实现...

class Answer(db.Model):

tablename = 'answer'

id = db.Column(db.Integer, primary_key=True, autoincrement=True)

content = db.Column(db.Text, nullable=False)

question_id = db.Column(db.Integer,db.ForeignKey('question.id'))

author_id = db.Column(db.Integer,db.ForeignKey('user.id'))

create_time = db.Column(db.DateTime,default=datetime.now)

question = db.relationship('Question',backref=db.backref('answers',order_by=id.desc()))

author = db.relationship('User',backref=db.backref('answers'))

@app.route('/add_awswer/',methods=['POST'])

def and_awser():

content = request.form.get('answer_content')

question_id = request.form.get('question_id')

answer = Answer(content=content)

userId = session['user_id']

user = User.query.filter(User.id == userId).first()

answer.author = user

question = Question.query.filter(Question.id == question_id).first()

answer.question = question

db.session.add(answer)

db.session.commit()

return redirect(url_for('detail',question_id = question_id))

本人菜鸟，我想在模板中获取 Answer 模型中总共有多少条数据