from flask import Flask import os from flask_sqlalchemy import SQLAlchemy import pymysql app=Flask(__name__)#__name__當前文件 BASE_DIR=os.path.abspath(os.path.dirname(__file__))#路徑abspath絕對路徑abspath;dirname目錄名dirname,dirname #BASE_DIR=當前文件的絕對路徑 #base基礎base;dir目錄dir;base_dir基礎目錄base_dir;base_dir基礎目錄base_dir app.config["SQLALCHEMY_DATABASE_URI"]="mysql+pymysql://root:root@127.0.0.1:3306/student" #app.config['SQLALCHEMY_DATABASE_URI']="sqlite:///"+os.path.join(BASE_DIR,"Demo.sqlite")#demo演示demo;數據庫指向自帶的sqlite數據庫 #config配置，布局;config,config配置config#sqlite,django和flask自帶的數據庫sqlite一個輕量級的數據庫sqlite #databases數據庫databases;sqlalchemy功能，關系，外鍵關聯，中進行關聯查詢sqlalchemy,sqlalchemy #URI統(tǒng)一資源匹配符；配置數據連接的參數#app.config返回類字典對象，里面用來存放當前app的配置 app.config["SQLALCHEMY_COMMIT_TEARDOWN"]=True#teardown拆卸，待拆房屋,teardown,teardown #commit把...交托給commit把...交托給commit commit #sqlalchemy commit teardown請求結束后自動提交數據庫修改 app.config["SQLALCHEMY_TRACK_MODIFICATIONS"]=True#track軌道，追蹤track,track,track，track,track； #modifications#修改修飾modifications,modifications; #如果設置成True(默認情況),flask_SQLALchemy 將會追蹤對象的修改并且發(fā)送信號 models=SQLAlchemy(app)#關聯sqlcchemhy和flask應用 session=models.session() class BaseModel(models.Model):#學員表__abstract__=True#抽象表為True,代表當前類為抽象類，不會被實例化id=models.Column(models.Integer,primary_key=True,autoincrement=True)def save(self):session.add(self)session.commit()def delete_obj(self):#魔術方法session.delete(self)session.commit() class Students(BaseModel):#學員表__tablename="students"name=models.Column(models.String(32))age=models.Column(models.Integer)gender=models.Column(models.Integer)#0,男；1女；2其他 class Course(BaseModel):#課程表__tablename = "course"label = models.Column(models.String(32))description=models.Column(models.Text)#雙向映射# teachers=models.relationship(# 'course',#映射類的名稱#雙向映射# backref='teachers'#映射到教師表# ) class Stu_Cou(BaseModel):#課程表__tablename = "stu_cou"course_id = models.Column(models.Integer, models.ForeignKey("course.id"))student_id = models.Column(models.Integer, models.ForeignKey("students.id")) class Grade(BaseModel):#成績表，課程、學員關聯此表__tablename = "grade"id = models.Column(models.Integer, primary_key=True, autoincrement=True)grade=models.Column(models.Float)course_id=models.Column(models.Integer,models.ForeignKey("course.id"))student_id = models.Column(models.Integer, models.ForeignKey("students.id")) class Attendance(BaseModel):#考勤表 關聯學員__tablename = "attendance"id = models.Column(models.Integer, primary_key=True, autoincrement=True)student_id = models.Column(models.Integer, models.ForeignKey("students.id"))att_time=models.Column(models.Date)status = models.Column(models.Integer,default=1)#0遲到；1正常出勤；2早退；3請假；4曠課 class Teachers(BaseModel):#教師表__tablename = "teachers"id = models.Column(models.Integer, primary_key=True, autoincrement=True)name = models.Column(models.String(32))age = models.Column(models.Integer)gender = models.Column(models.Integer) # 0,男；1女；2其他course_id = models.Column(models.Integer, models.ForeignKey("course.id")) # session=models.session()#創(chuàng)建一個數據庫修改實例，增刪改 # course=Course(label="python",description="python是世界上最好的語言") # session.add(course) # session.commit()#提交保存 #添加數據 # t=Teachers(name="老邊",age=24,gender=0,course_id=1) # t.save() # t1=Teachers() # t1.name="老王" # t1.gender=0 # t1.age=30 # t1.save() # t=Teachers(name="laoli",age=36,gender=1,course_id=1) # t.save() # t1=Teachers() # t1.name="老王" # t1.gender=1 # t1.age=45 # t1.save()#修改數據 # t=Teachers.query.get(1) # t.name="松哥帥" # t.gender=0 # t.age=18 # t.save() t=Teachers.query.get(7) t.name="松哥帥" t.gender=0 t.age=18 # #刪除數據 # t=Teachers.query.get(1) # t.delete_obj() # Teachers.query.get(2).delete_obj() # t=Teachers.query.get(3) # t.delete_obj() # Teachers.query.get(4).delete_obj() # t=Teachers.query.get(5) # t.delete_obj() # Teachers.query.get(6).delete_obj() # #查詢數據 # print(Teachers.query.all()) # print(Teachers.query.first()) # print(Teachers.query.filter_by(age=18).all()) # print(Teachers.query.all()) # print(Teachers.query.first()) # print(Teachers.query.filter_by(age=18).all()) # print(Teachers.query.order_by("age").all())#升序 # print(Teachers.query.order_by(models.desc("age")).all())#降序 # print(Teachers.query.get(3))#只能以主鍵查詢 # print(Teachers.query.offset(1).limit(2).all()) print(Teachers.query.offset(1).limit(2).all()) print(Teachers.query.get(3))#只能以主鍵查詢 print(Teachers.query.order_by(models.desc("age")).all())#降序 print(Teachers.query.order_by("age").all())#升序 # #offset偏移量，就是從哪里開始；limit限制條數，就是單次返回條數 # page=2 # page_size=4 # start=(page-1)*page_size # teachers=Teachers.query.offset(start).limit(page_size).all() # print(teachers)#模擬分頁顯示 page=2 page_size=4 start=(page-1)*page_size teachers=Teachers.query.offset(start).limit(page_size).all()# models.drop_all() # models.create_all() # course=Course(label="python",description="世界上最好的語言") # course.save() # course=Course(label="php",description="世界上將out的語言") # course.save() # course=Course(label="java",description="世界上快out的語言") # course.save()

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