app/models.py
"""_drh_"""
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy()
class Grade(db.Model):
#自增的主键id
id = db.Column(db.Integer, primary_key=True, autoincrement= True)
# 定义不能为空，且唯一的班级名称字段
g_name = db.Column(db.String(10), nullable = False, unique = True)
stus = db.relationship('Student', backref = 'p')
class Student(db.Model):
#定义id主键，自增字段
id = db.Column(db.Integer, primary_key=True, autoincrement=True)
#定义不能为空，且唯一的姓名字段
s_name = db.Column(db.String(10), unique=True, nullable=False)
#定义整型，默认为20的年龄字段
age = db.Column(db.Integer, default=20)
#定义关联表id的外键g_id
g_id = db.Column(db.Integer, db.ForeignKey('grade.id'),nullable = True)
__tablename__='stu'
def save(self):
db.session.add(self)
db.session.commit()
def delete(self):
db.session.delete(self)
db.session.commite()
c_s = db.Table('c_s',
db.Column('s_id', db.Integer, db.ForeignKey('stu.id')),
db.Column('c_id', db.Integer, db.ForeignKey('course.id'))
)
class Course(db.Model):
#自增的主键id
id = db.Column(db.Integer, primary_key=True, autoincrement= True)
# 定义不能为空，且唯一的班级名称字段
c_name = db.Column(db.String(10), nullable = False, unique = True)
stus = db.relationship('Student', secondary = c_s, backref = 'cou')
app/view.py
"""_drh_"""
from flask import Blueprint
from sqlalchemy import and_
from app.models import db, Student, Grade, Course
blue = Blueprint('app',__name__)
@blue.route('/')
def hello():
return 'hello1'
@blue.route('/create_db/')
def create_db():
db.create_all()
#删除表
#db.drop_all()
return '创建表成功'
@blue.route('/add_stu/')
def add_stu():
#新值学生数据
stu = Student()
stu.s_name = '小明'
stu.age = 20
db.session.add(stu)
db.session.commit()
return '提交成功'
@blue.route('/add_stus/')
def add_stus():
stu_list=[]
for i in range(10):
stu = Student()
stu.s_name = 'xiaohpng' +str(i)
stu.age = int(i)
stu_list.append(stu)
#db.session.add(stu)
db.session.add_all(stu_list)
db.session.commit()
return '批量插入成功'
@blue.route('/sel_stu/')
def sel_stu():
#select * from stu where s_name='xiaopng0'
stu=Student.query.filter_by(s_name='xiaohpng0').first()
print(stu.s_name)
print(stu.age)
return '查询数据成功！'
@blue.route('/del_stu/')
def del_stu():
#删除年龄0的信息
stus = Student.query.filter_by(age=0).all()
for stu in stus:
db.session.delete(stu)
db.session.commit()
return '删除成功！'
@blue.route('/update_stu/')
def update_stu():
#获取对象
stu = Student.query.filter_by(s_name='xiaopng1').first()
stu.age = 100
stu.s_name = 'xiaohong'
#db.session.add(me) 可以不写
#db.session.commit()
stu.save()
return '修改成功！'
@blue.route('/sel_stus/')
def sel_stus():
stu = Student.query.filter(Student.s_name == 'xiaohpng1').first()
print(stu)
#查询所有学生信息
#all()结果为列表，列表中的元素为查询的学生对象
stus = Student.query.all()
print(stus)
stu = Student.query.filter(Student.id == '1').first()
print(stu)
#排序 order_by
stus = Student.query.order_by(-Student.id).all() #降序
stus = Student.query.order_by(Student.id).all() #升序
print(stus)
#offset limit
stus = Student.query.limit(3).all()
page = 1
stus = Student.query.offset((page-1)*3).limit(2).all()
#大于gt 小于lt
#大于等于ge 小于等于le
stus = Student.query.filter(Student.age.__ge__(10)).all()
#where id in [1,2,3,4]
stus = Student.query.filter(Student.id.in_([1,2,3,4])).all()
stus = Student.query.filter(Student.age >= 10).all()
print(stu)
stu = Student.query.filter(Student.age==2,
Student.s_name.like('xiao%')).all() #多条件查询
stu = Student.query.filter(Student.age == 2 or
Student.s_name.like('xiao%')).all()
# and 或者 or
return '查询学生信息'
#5day
@blue.route('/add_grade/')
def add_grade():
grades_name = ['Python', 'Jave','VHDL','C++']
for name in grades_name:
g = Grade()
g.g_name = name
db.session.add(g)
db.session.commit()
return '新增班级成功！'
@blue.route('/add_stu_grade/')
def add_stu_grade():
#给学生分配班级
stus = Student.query.filter(Student.id.in_([1,5,6])).all()
for stu in stus:
#分配给python班
stu.g_id = 1
stu.save()
return '分配班级成功！'
@blue.route('/sel_stu_by_grade/')
def sel_stu_grade():
# 通过班级查询学生的信息
g = Grade.query.filter(Grade.g_name == 'Python').first()
print (g.stus)
stu_names = [stu.s_name for stu in g.stus ]
print(stu_names)
return '通过班级查询学生成功！'
@blue.route('/sel_grade_by_stu/')
def sel_grade_by_stu():
stu = Student.query.filter(Student.s_name == 'xiaohpng0').first()
print (stu.g_id)
#g = Grade.query.get(stu.g_id)
print (stu.p)
return '通过学生查询班级成功！'
@blue.route('/add_cou/')
def add_cou():
course_names = ['物理', '高数', '英语']
for name in course_names:
cou = Course()
cou.c_name = name
db.session.add(cou)
db.session.commit()
return '创建课程表成功！'
@blue.route('/add_cou_to_stu/')
def add_cou_to_stu():
# 学生添加课程
# 给id = 1的学生添加线代高数课程
stu = Student.query.get(1)
print(stu.cou)
cou1 = Course.query.filter(Course.c_name == '物理').first()
cou2 = Course.query.filter(Course.c_name == '高数').first()
# stu.cou 返回的值为学生选择的课程对象组成的列表结果
stu.cou.append(cou1)
stu.cou.append(cou2)
# 提交
db.session.commit()
return '学生添加课程成功！'
@blue.route('/del_stu_cou/')
def del_stu_cou():
stu = Student.query.get(1)
cou2 = Course.query.filter(Course.c_name == '高数').first()
#删除remove
stu.cou.remove(cou2)
db.session.commit()
return '删除课程成功！'
manage.py
from flask import Flask
from flask_script import Manager
from app.models import db
from app.views import blue
app = Flask(__name__)
app.register_blueprint(blueprint=blue)
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql+pymysql://root:[email protected]:3306/flask9'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
db.init_app(app)
manage = Manager(app)
if __name__ == '__main__':
manage.run()
