{"id":2134,"date":"2021-08-03T20:18:06","date_gmt":"2021-08-03T12:18:06","guid":{"rendered":"https:\/\/egonlin.com\/?p=2134"},"modified":"2022-02-07T14:28:58","modified_gmt":"2022-02-07T06:28:58","slug":"%e6%95%b0%e6%8d%ae%e5%ba%93","status":"publish","type":"post","link":"https:\/\/egonlin.com\/?p=2134","title":{"rendered":"\u6570\u636e\u5e93"},"content":{"rendered":"

05-\u6570\u636e\u5e93<\/h1>\n

\"\"<\/div><\/p>\n

\u6570\u636e\u5e93\uff0c\u987e\u540d\u601d\u4e49\u662f\u50a8\u5b58\u6570\u636e\u7684\u4ed3\u5e93\uff0c\u5e38\u89c1\u7684\u7ba1\u7406\u6570\u636e\u5e93\u7684\u8f6f\u4ef6\u88ab\u79f0\u4e3a\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\uff08DBMS, Database Management System\uff09, \u5e38\u89c1\u7684DBMS\u6709 MySQL\u3001PostgreSQL\u3001SQLite\u3001MongoDB\u3002\u8fd9\u4e9b\u5e38\u89c1\u7684DBMS\u6211\u4eec\u53ef\u4ee5\u628a\u4ed6\u4eec\u7406\u89e3\u4e3a\u4e13\u95e8\u8d1f\u8d23\u642c\u8fd0\u6570\u636e\u7684\u7ba1\u7406\u7684\u6570\u636e\u7684\u7a0b\u5e8f\u3002<\/p>\n

1 \u4ec0\u4e48\u662fORM\uff1f<\/h1>\n

\"\"<\/div><\/p>\n

\u5bf9\u8c61\u5173\u7cfb\u6620\u5c04\uff08\u82f1\u8bed\uff1a(Object Relational Mapping<\/strong>\uff0c\u7b80\u79f0ORM<\/strong>\uff0c\u6216O\/RM<\/strong>\uff0c\u6216O\/R mapping<\/strong>\uff09\uff0c\u662f\u4e00\u79cd\u7a0b\u5e8f\u6280\u672f\uff0c\u7528\u4e8e\u5b9e\u73b0\u9762\u5411\u5bf9\u8c61\u7f16\u7a0b\u8bed\u8a00\u91cc\u4e0d\u540c\u7c7b\u578b\u7cfb\u7edf\u7684\u6570\u636e\u4e4b\u95f4\u7684\u8f6c\u6362 \u3002 ORM\u662f\u201c\u5bf9\u8c61-\u5173\u7cfb-\u6620\u5c04\u201d\u7684\u7b80\u79f0\u3002\u5728\u6211\u4eec\u7684web\u5e94\u7528\u5f00\u53d1\u4e2dORM\u628a\u5e95\u5c42\u7684SQL\u6570\u636e\u5b9e\u4f53\u8f6c\u5316\u6210\u9ad8\u5c42\u7684Python\u5bf9\u8c61\u3002\u53ea\u9700\u8981\u901a\u8fc7Python\u4ee3\u7801\u5373\u53ef\u5b8c\u6210\u6570\u636e\u5e93\u64cd\u4f5c\u3002<\/p>\n

2 \u4e3a\u4ec0\u4e48\u8981\u6709ORM?<\/h1>\n

\u5728web\u5e94\u7528\u91cc\u4f7f\u7528\u539f\u751f\u7684SQL\u8bed\u53e5\u64cd\u4f5c\u6570\u636e\u5e93\u56fa\u7136\u80fd\u8fbe\u5230\u6211\u4eec\u5904\u7406\u50a8\u5b58\u6570\u636e\u7684\u9700\u6c42\uff0c\u4f46\u662f\u4f1a\u5b58\u5728\u4ee5\u4e0b\u4e09\u7c7b\u95ee\u9898\uff1a<\/p>\n

    \n
  • \u624b\u52a8\u7f16\u5199SQL\u8bed\u53e5\u6bd4\u8f83\u590d\u6742\u8017\u65f6\uff08\u5f53\u7136\u56e0\u4eba\u800c\u5f02\uff0c\u5982\u679c\u70ed\u8877\u4e8e\u539f\u751fsql\uff0c\u5e76\u4e0d\u5f71\u54cd\u5f00\u53d1\uff09\uff0c\u5e76\u4e14\u89c6\u56fe\u51fd\u6570\u4e2d\u5199\u5927\u91cfSQL\u8bed\u53e5\u4f1a\u964d\u4f4e\u4ee3\u7801\u7684\u6613\u8bfb\u6027\u3002<\/li>\n
  • \u6bd4\u8f83\u5bb9\u6613\u51fa\u73b0\u5b89\u5168\u95ee\u9898\uff0c\u5982SQL\u6ce8\u5165\u3002<\/li>\n
  • \u5bf9\u4e8e\u4e0d\u540c\u7684DBMS\uff0c\u9700\u8981\u4f7f\u7528\u4e0d\u540c\u7684Python\u63a5\u53e3\u5e93\uff0c\u8bed\u6cd5\u5404\u4e0d\u76f8\u540c\uff0c\u5f88\u96be\u6709\u6807\u51c6\u5316\u7684\u4ee3\u7801\u6d41\u7a0b\u3002<\/li>\n<\/ul>\n

    \u4f7f\u7528ORM\u53ef\u4ee5\u5f88\u5927\u7a0b\u5ea6\u4e0a\u89e3\u51b3\u8fd9\u4e9b\u95ee\u9898\uff0c\u5728python\u4e2d\uff0cORM\u628a\u5e95\u5c42\u7684SQL\u6570\u636e\u5b9e\u4f53\u8f6c\u5316\u6210\u9ad8\u5c42\u7684Python\u5bf9\u8c61\u3002\u8fd9\u6837\u7684\u597d\u5904\u662f\uff0c\u4f60\u751a\u81f3\u4e0d\u9700\u8981\u4e86\u89e3SQL\uff0c\u53ea\u9700\u8981\u64cd\u4f5cPython\u5bf9\u8c61\u7684\u5373\u53ef\u5b8c\u6210\u6570\u636e\u5e93\u64cd\u4f5c\u3002<\/p>\n

    \u4f7f\u7528ORM\u7684\u4f18\u52bf\uff1a<\/strong><\/p>\n

      \n
    • \u63d0\u5347\u5f00\u53d1\u6548\u7387\u3002\u4ece\u9ad8\u5c42\u5bf9\u8c61\u8f6c\u6362\u6210\u539f\u751fSQL\u4f1a\u727a\u7272\u4e00\u4e9b\u6027\u80fd\uff0c\u4f46\u8fd9\u5fae\u4e0d\u8db3\u9053\u7684\u6027\u80fd\u727a\u7272\u6362\u53d6\u7684\u662f\u5de8\u5927\u5f00\u53d1\u6548\u7387\u63d0\u5347\u3002<\/li>\n
    • \u53ef\u79fb\u690d\u6027\u597d\u3002\u5b83\u5b9e\u73b0\u4e86\u6570\u636e\u5e93\u6a21\u578b\u4e0eDEMS\u7684\u89e3\u8026\uff0c\u5373\u6570\u636e\u6a21\u578b\u7684\u8bbe\u8ba1\u4e0d\u9700\u8981\u4f9d\u8d56\u4e8e\u7279\u5b9a\u7684\u6570\u636e\u5e93\uff0c\u901a\u8fc7\u7b80\u5355\u7684\u914d\u7f6e\u5c31\u53ef\u4ee5\u8f7b\u677e\u66f4\u6362\u6570\u636e\u5e93\u3002\u901a\u5e38\u4e00\u4e2aorm\u652f\u6301\u5f88\u591a\u7684DEMS\uff0c\u59821MySQL\u3001PostgreSQL\u3001Oracle\u3001SQLite\u7b49\uff0c\u8fd9\u6781\u5927\u7684\u51cf\u8f7b\u4e86\u5f00\u53d1\u4eba\u5458\u7684\u5de5\u4f5c\u91cf\uff0c\u4e0d\u9700\u8981\u9762\u5bf9\u56e0\u6570\u636e\u5e93\u53d8\u66f4\u800c\u5bfc\u81f4\u7684\u65e0\u6548\u52b3\u52a8\u3002<\/li>\n<\/ul>\n

      3 \u5982\u4f55\u5728Flask\u5e94\u7528ORM\uff1f<\/h1>\n

      \u9009\u62e9ORM\u6846\u67b6\u65f6\uff0c\u5728\u6211\u4eecFlask\u4e2d\u66f4\u63a8\u8350\u4f7f\u7528Flask\u7684\u6269\u5c55\u7ec4\u4ef6Flask-SQLchemy \u3002Python\u5b9e\u73b0\u7684ORM\u6709SQLAlchemy\u3001Peewee\u3001PonyORM\u7b49\uff0c\u5176\u4e2dSQLAlchemy\u662fPython\u793e\u533a\u4f7f\u7528\u6700\u5e7f\u6cdb\u7684ORM\u4e4b\u4e00\uff0cFlask-SQLchemy\u6b63\u662f\u57fa\u4e8eSQLchemy\u3002<\/p>\n

      \"\"<\/div><\/p>\n

      3.1 \u8fde\u63a5\u6570\u636e\u5e93\uff1a<\/h2>\n

      \u9996\u5148\u5207\u5165\u5230\u6211\u4eec\u7684\u865a\u62df\u73af\u5883 \uff0c\u5b89\u88c5\u6211\u4eec\u7684 Flask-SQLchemy<\/code><\/p>\n

      pip install flask-sqlalchemy\npip install pymysql<\/code><\/pre>\n
      \u8fd9\u91cc\u6211\u4eec\u7684DBMS<\/code>\u4ee5mysql<\/code>\u6570\u636e\u5e93\u4e3a\u4f8b\uff0c \u8fde\u63a5\u6570\u636e\u5e93<\/p>\n
      \u5b9e\u4f8b<\/strong><\/p>\n
      from flask import Flask\nfrom flask_sqlalchemy import SQLAlchemy\n\napp = Flask(__name__)\nHOST = '127.0.0.1'\nPORT = '3306'\nDATABASE_NAME = '01_db'\nUSERNAME = 'root'\nPASSWORD = 'root'\n\nDB_URI = "mysql+pymysql:\/\/{username}:{password}@{host}:{port}\/{databasename}?charset=utf8mb4"\\\n.format(username=USERNAME,password=PASSWORD,host=HOST,port=PORT,databasename=DATABASE_NAME)\n\napp.config['SQLALCHEMY_DATABASE_URI'] = DB_URI\napp.config['SQLALCHEMY_TRACK_MODIFICATIONS']= False\n\ndb = SQLAlchemy(app)<\/code><\/pre>\n
      \u89e3\u8bfb\uff1a<\/strong><\/p>\n
      1<\/strong>  \u4eceflask_sqlalchemy<\/code>\u6a21\u5757\u4e2d\u5bfc\u5165SQLAlchemy<\/code>\u7c7b<\/p>\n
      from flask_sqlalchemy import SQLAlchemy<\/code><\/pre>\n
      2<\/strong>  app\u5bf9\u8c61\u901a\u8fc7\u53d8\u91cfSQLALCHEMY_DATABASE_URI<\/code>\u52a0\u8f7d\u914d\u7f6e\u597d\u7684URI<\/code>(\u7edf\u4e00\u8d44\u6e90\u6807\u8bc6\u7b26)\uff0cURI\u5185\u5305\u542b\u4e86\u5404\u79cd\u7528\u4e8e\u8fde\u63a5\u6570\u636e\u5e93\u7684\u4fe1\u606f\uff0c\u6307\u5411\u4e00\u4e2a\u5177\u4f53\u7684\u5e93\u3002<\/p>\n
      \u5e38\u7528\u6570\u636e\u5e93\u7684URI\u683c\u5f0f<\/p>\n
      HOST = '127.0.0.1'  # ip\nPORT = '3306'     # \u7aef\u53e3\nUSERNAME = 'root' # \u6570\u636e\u5e93\u8d26\u53f7\nPASSWORD = 'root'   # \u5bc6\u7801\nDATABASE_NAME = '01_db'  # \u5177\u4f53\u7684\u4e00\u4e2a\u5e93\u540d\nDB_URI = "mysql+pymysql:\/\/{username}:{password}@{host}:{port}\/{databasename}?charset=utf8mb4"\\\n.format(username=USERNAME,password=PASSWORD,host=HOST,port=PORT,databasename=DATABASE_NAME)\n\napp.config['SQLALCHEMY_DATABASE_URI'] = DB_URI<\/code><\/pre>\n
      3<\/strong> SQLALCHEMY_TRACK_MODIFICATIONS<\/code>\u8fd9\u4e2a\u914d\u7f6e\u53d8\u91cf\u51b3\u5b9a\u662f\u5426\u8ffd\u8e2a\u5bf9\u8c61\u7684\u4fee\u6539\uff0c\u8fd9\u7528\u4e8eFLask-    SQLALchemy\u7684\u4e8b\u4ef6\u901a\u77e5\u7cfb\u7edf\u3002\u8fd9\u4e2a\u914d\u7f6e\u952e\u9ed8\u8ba4\u503c\u4e3aNone<\/code>\uff0c\u5982\u679c\u6ca1\u6709\u7279\u6b8a\u9700\u8981\u6211\u4eec\u628a\u5b83\u8bbe\u7f6e\u4e3aFlase<\/code>,  \u907f\u514d\u9020\u6210\u4e00\u4e9b\u6ca1\u5fc5\u8981\u7684\u6027\u80fd\u6d6a\u8d39\u3002<\/p>\n
      app.config['SQLALCHEMY_TRACK_MODIFICATIONS']= False<\/code><\/pre>\n
      4<\/strong> SQLAlchemy<\/code>\u7c7b\u4f20\u5165app<\/code>\u7c7b\uff0c\u5f15\u7528app<\/code>\u914d\u7f6e\u5b9a\u4f4d\u5230\u5177\u4f53\u7684\u6570\u636e\u5e93\uff0c\u5e76\u4e14\u5b9e\u4f8b\u5316\u51fadb<\/code>\u5bf9\u8c61\uff0c\u8fd9\u4e2adb\u5bf9\u8c61\u4ee3\u8868\u6211\u4eec\u7684\u6570\u636e\u5e93\uff0c\u5e76\u4e14\u901a\u8fc7\u8fd9\u4e2a\u5bf9\u8c61\u64cd\u4f5c\u6211\u4eec\u7684ORM<\/code><\/p>\n
      db = SQLAlchemy(app)<\/code><\/pre>\n
      3.2 \u6570\u636e\u5e93\u6a21\u578b<\/h2>\n
      \"\"<\/div><\/p>\n
      3.2.1 \u4ec0\u4e48\u662f\u6570\u636e\u5e93\u6a21\u578b\uff1f<\/strong><\/h3>\n
      \u7ee7\u627f\u4e86db.Model\u7684python\u7c7b\uff0c\u5e76\u4e14\u8fd9\u4e2apython\u7c7b\u6620\u5c04\u5230\u6570\u636e\u5e93\u4e3a\u4e00\u4e2a\u8868\uff0c\u8fd9\u4e2apython\u7c7b\u79f0\u4e4b\u4e3a\u6570\u636e\u5e93\u6a21\u578b\u3002\u6bcf\u4e2a\u6570\u636e\u5e93\u6a21\u578b\u90fd\u5bf9\u5e94\u7740\u6570\u636e\u5e93\u4e2d\u7684\u4e00\u4e2a\u8868\u3002<\/p>\n
      3.2.2 \u6570\u636e\u5e93\u6a21\u578b\u5b9e\u4f8b\uff1a<\/strong><\/h3>\n
      class UserInfo(db.Model):\n    __tablename__ = 'user_info'\n    id = db.Column(db.Integer,primary_key=True,autoincrement=True)\n    username = db.Column(db.String(20),nullable=False)<\/code><\/pre>\n
        \n
      • __tablename__<\/code>\u53ef\u4ee5\u76f4\u63a5\u6307\u5b9a\u8868\u540d\uff08\u63a8\u8350\u4f7f\u7528\uff09\u3002\u5982\u679c\u6ca1\u6709\u5199__tablename__<\/code>\u6307\u5b9a\u8868\u540d\uff0c\u6b64\u7c7b\u540d\u53ef\u4ee5\u81ea\u52a8\u8f6c\u5316\u4e3a\u8868\u540d\uff08\u4e0d\u63a8\u8350\u4f7f\u7528\uff09\u3002\n
          \n
        • \u7c7b\u540d\u81ea\u52a8\u8f6c\u5316\u8868\u540d\u7684\u65b9\u5f0f\u4e3aUser<\/code>–> user<\/code># \u5355\u4e2a\u5355\u8bcd\u8f6c\u6362\u4e3a\u5c0f\u5199
          \nUserInfo<\/code>–> user_info<\/code># \u591a\u4e2a\u5355\u8bcd\u8f6c\u6362\u4e3a\u5c0f\u5199\u5e76\u4f7f\u7528\u4e0b\u5212\u7ebf\u5206\u9694<\/li>\n
        • \u5982UserInfo\u7c7b\u5728\u6ca1\u6709 __tablename__<\/code>\u6307\u5b9a\u8868\u540d\u65f6\u5019\uff0cUserInfo\u7c7b\u4f1a\u81ea\u52a8\u6620\u5c04\u5230\u6570\u636e\u5e93\u7684\u8868\u540d\u4e3auser_info<\/code>\u3002<\/li>\n<\/ul>\n<\/li>\n
        •  db.Column<\/code>\u7c7b\u5b9e\u4f8b\u5316\u8868\u793a\u5b57\u6bb5\uff08\u8868\u793a\u6570\u636e\u5e93\u4e2d\u7684\u5217\uff09\uff0c\u8be5\u7c7b\u5b9e\u4f8b\u5316\u51fa\u7684\u5bf9\u8c61\u88ab\u4e00\u4e2a\u53d8\u91cf\u63a5\u53d7\uff0c\u8be5\u53d8\u91cf\u8868\u793a\u5b57\u6bb5\u540d\u3002\u8be5\u7c7b\u5b9e\u4f8b\u5316\u65f6\u4f20\u5165\u7684\u53c2\u6570\u8868\u793a\u5b57\u6bb5\u7684\u7ea6\u675f\u3002\n
            \n
          • \u5982\uff1aid = db.Column(db.Integer,primary_key=True,autoincrement=True)<\/code>\u8868\u793a\u8be5\u8868\u5185id\u5b57\u6bb5\u4e3a\u4e3b\u952e\u5e76\u4e14\u81ea\u52a8\u589e\u957f\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
            \"\"<\/div><\/p>\n
            3.2.3 \u5e38\u7528\u7684\u5b57\u6bb5\u7c7b\u578b\u8868\uff1a<\/strong><\/h3>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
            \u5b57\u6bb5<\/th>\n\u8bf4\u660e<\/th>\n\u6620\u5c04\u5230\u6570\u636e\u5e93\u5bf9\u5e94\u7c7b\u578b<\/th>\n<\/tr>\n<\/thead>\n
            Integer<\/td>\n\u6574\u6570<\/td>\nint\u7c7b\u578b<\/td>\n<\/tr>\n
            String<\/td>\n\u5b57\u7b26\u4e32\uff0cString<\/code>\u7c7b\u5185\u53ef\u9009\u62e9length<\/code>\u53c2\u6570\u7684\u503c\u7528\u4e8e\u8bbe\u7f6e\u6700\u5927\u5b57\u7b26\u4e2a\u6570<\/td>\nvarchar\u7c7b\u578b<\/td>\n<\/tr>\n
            Text<\/td>\n\u7528\u4e8e\u50a8\u5b58\u8f83\u957f\u7684Unicode\u6587\u672c\uff0c,\u7406\u8bba\u4e0a\u53ef\u4ee5\u50a8\u5b5865535\u4e2a\u5b57\u8282<\/td>\ntext\u7c7b\u578b<\/td>\n<\/tr>\n
            Date<\/td>\n\u65e5\u671f\uff0c\u5b58\u50a8Python<\/code>\u7684datetime.date<\/code> \u5bf9\u8c61<\/td>\ndate\u7c7b\u578b<\/td>\n<\/tr>\n
            Time<\/td>\n\u65f6\u95f4\uff0c\u5b58\u50a8Python<\/code>\u7684datetime.time<\/code> \u5bf9\u8c61<\/td>\ntime\u7c7b\u578b<\/td>\n<\/tr>\n
            DateTime<\/td>\n\u65f6\u95f4\u548c\u65e5\u671f\uff0c\u5b58\u50a8Python<\/code> \u7684datetime<\/code> \u5bf9\u8c61<\/td>\ndatetime\u7c7b\u578b<\/td>\n<\/tr>\n
            Float<\/td>\n\u6d6e\u70b9\u7c7b\u578b<\/td>\nfloat\u7c7b\u578b<\/td>\n<\/tr>\n
            Double<\/td>\n\u53cc\u7cbe\u5ea6\u6d6e\u70b9\u7c7b\u578b\uff0c\u6bd4\u6d6e\u70b9\u7c7b\u578b\u5c0f\u6570\u4f4d\u7cbe\u5ea6\u66f4\u9ad8\u3002<\/td>\ndouble\u7c7b\u578b\uff0c\u5360\u636e64\u4f4d\u3002<\/td>\n<\/tr>\n
            Boolean<\/td>\n\u5e03\u5c14\u503c<\/td>\ntinyint\u7c7b\u578b<\/td>\n<\/tr>\n
            Enum<\/td>\n\u679a\u4e3e\u7c7b\u578b<\/td>\nenum\u7c7b\u578b<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
            \"\"<\/div><\/p>\n
            3.2.4 <\/strong>Column\u5e38\u7528\u53c2\u6570\u8868\uff1a<\/h3>\n\n\n\n\n\n\n\n\n\n\n\n\n\n
            \u7ea6\u675f<\/th>\n\u8bf4\u660e<\/th>\n<\/tr>\n<\/thead>\n
            primary_key<\/td>\n\u5982\u679c\u8bbe\u4e3aTrue\uff0c\u8be5\u5217\u5c31\u662f\u8868\u7684\u4e3b\u952e<\/td>\n<\/tr>\n
            unique<\/td>\n\u5982\u679c\u8bbe\u4e3aTrue\uff0c\u8be5\u5217\u6bcf\u4e2a\u503c\u552f\u4e00\uff0c\u4e5f\u5c31\u662f\u8be5\u5b57\u6bb5\u4e0d\u5141\u8bb8\u51fa\u73b0\u91cd\u590d\u503c<\/td>\n<\/tr>\n
            index<\/td>\n\u5982\u679c\u8bbe\u4e3aTrue\uff0c\u4e3a\u8fd9\u5217\u521b\u5efa\u7d22\u5f15\uff0c\u7528\u4e8e\u63d0\u5347\u67e5\u8be2\u6548\u7387<\/td>\n<\/tr>\n
            nullable<\/td>\n\u5982\u679c\u8bbe\u4e3aTrue\uff0c\u8fd9\u5217\u5141\u8bb8\u4f7f\u7528\u7a7a\u503c\uff0c\u53cd\u4e4b\u5219\u4e0d\u5141\u8bb8\u4f7f\u7528\u7a7a\u503c\u3002<\/td>\n<\/tr>\n
            server_default<\/td>\n\u4e3a\u8fd9\u5217\u5b9a\u4e49\u9ed8\u8ba4\u503c,  \u9ed8\u8ba4\u503c\u53ea\u652f\u6301\u5b57\u7b26\u4e32\uff0c\u5176\u4ed6\u7c7b\u578b\u9700\u8981db.text()\u65b9\u6cd5\u6307\u5b9a<\/td>\n<\/tr>\n
            default<\/td>\n\u4e3a\u8fd9\u5217\u5b9a\u4e49\u9ed8\u8ba4\u503c\uff0c\u4f46\u662f\u8be5\u7ea6\u675f\u5e76\u4e0d\u4f1a\u771f\u6b63\u6620\u5c04\u5230\u8868\u7ed3\u6784\u4e2d\uff0c\u8be5\u7ea6\u675f\u53ea\u4f1a\u5728ORM\u5c42\u9762\u5b9e\u73b0(\u4e0d\u63a8\u8350\u4f7f\u7528)<\/td>\n<\/tr>\n
            comment<\/td>\n\u8be5\u5b57\u6bb5\u7684\u6ce8\u91ca<\/td>\n<\/tr>\n
            name<\/td>\n\u53ef\u4ee5\u4f7f\u7528\u8be5\u53c2\u6570\u76f4\u63a5\u6307\u5b9a\u5b57\u6bb5\u540d<\/td>\n<\/tr>\n
            autoincrement<\/td>\n\u8bbe\u7f6e\u8fd9\u4e2a\u5b57\u6bb5\u4e3a\u81ea\u52a8\u589e\u957f\u7684\u3002<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
            server_default\u5e38\u7528\u914d\u7f6e<\/strong><\/h5>\n\n\n\n\n\n\n\n\n
            \u914d\u7f6e\u9ed8\u8ba4\u503c\u7c7b\u578b<\/th>\n\u4ee3\u7801<\/th>\n<\/tr>\n<\/thead>\n
            \u66f4\u65b0datatime\u65f6\u95f4<\/td>\nserver_default = db.text("CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP")<\/td>\n<\/tr>\n
            \u5f53\u524d\u7684datatime\u65f6\u95f4<\/td>\nserver_default = db.text("CURRENT_TIMESTAMP")<\/td>\n<\/tr>\n
            \u6570\u5b57<\/td>\nserver_default=\u201c\u6570\u5b57\u201d<\/td>\n<\/tr>\n
            \u5e03\u5c14<\/td>\nserver_default=db.text(‘True’) \/ server_default=db.text(‘False’)\/ server_default=’\u6570\u5b57’<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
            \"\"<\/div><\/p>\n
            3.2.5 \u5c06\u5199\u597d\u7684\u6a21\u578b\u6620\u5c04\u5230\u6570\u636e\u5e93\u3002<\/strong><\/h3>\n
            class UserInfo(db.Model):\n    __tablename__ = 'user_info'\n    id = db.Column(db.Integer,primary_key=True,autoincrement=True)\n    username = db.Column(db.String(20),nullable=False)\n\ndb.create_all()<\/code><\/pre>\n
            \u5982\u679c\u4f60\u5df2\u7ecf\u5b9a\u4e49\u597d\u4e86\u4e00\u4e2a\u7ee7\u627fdb.Model<\/code>\u7684\u7c7b\uff0c\u6211\u4eec\u628a\u8fd9\u4e2a\u7c7b\u79f0\u4e4b\u4e3a\u6a21\u578b\u3002\u6211\u4eec\u60f3\u628a\u8fd9\u4e2a\u6a21\u578b\u6620\u5c04\u5230\u6570\u636e\u5e93\u4e2d\uff0c\u4e5f\u5c31\u662f\u5728\u6570\u636e\u5e93\u4e2d\u521b\u5efa\u8fd9\u4e2a\u6a21\u578b\u6240\u63cf\u8ff0\u7684\u4e00\u5f20\u8868\uff0c\u4f7f\u7528db.create_all()<\/code>\u53ef\u4ee5\u5b9e\u73b0\u628a\u7ee7\u627f\u4e86\u8be5db.model<\/code>\u7684\u6240\u6709\u6a21\u578b\u521b\u5efa\u5230\u6570\u636e\u5e93\u4e2d\u3002\u67e5\u770b\u6570\u636e\u5e93\u7684\u65f6\u5019\u6211\u4eec\u4f1a\u53d1\u73b0\u591a\u4e86\u4e00\u5f20user_info<\/code>\u8868\u3002<\/p>\n
            \"\"<\/div><\/p>\n
            3.2.6 \u66f4\u65b0\u6a21\u578b<\/h3>\n
            \u5982\u679c\u6211\u4eec\u8981\u66f4\u65b0\u4e00\u4e2a\u6a21\u578b\uff0c\u5e76\u4e14\u60f3\u628a\u8fd9\u4e2a\u65b0\u7684\u6a21\u578b\u6620\u5c04\u5230\u6570\u636e\u5e93\u4e2d\uff0c\u76f4\u63a5\u4f7f\u7528db.create_all()<\/code>\u4f1a\u65e0\u6548\uff0c\u56e0\u4e3a\u539f\u6765\u5df2\u7ecf\u5b58\u5728\u4e86\u8fd9\u5f20\u8868\uff0c\u4e3a\u4e86\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\u6211\u4eec\u53ef\u4ee5\u5148db.drop_all()<\/code>\u5220\u9664\u8be5\u5e93\u4e0b\u7684\u6240\u6709\u7ee7\u627f\u4e86db.model<\/code>\u7684\u6a21\u578b\u8868\uff0c\u7136\u540e\u518ddb.create_all()<\/code>\u4f7f\u5f97\u7ee7\u627f\u4e86db.model<\/code>\u7684\u6240\u6709\u6a21\u578b\u8868\u6620\u5c04\u5230\u6570\u636e\u5e93\u4e2d\uff0c\u4ece\u800c\u521b\u5efa\u6211\u4eec\u66f4\u65b0\u7684\u8868\u3002\u8fd9\u79cd\u65b9\u5f0f\u7684\u539f\u7406\u662f\u5148\u5220\u9664\u6570\u636e\u5e93\u4e2d\u539f\u6765\u6240\u6709\u7684\u6a21\u578b\u8868\uff0c\u7136\u540e\u5728\u65b0\u5efa\u6240\u6709\u9700\u8981\u6620\u5c04\u7684\u6a21\u578b\u8868\uff0c\u8fd9\u79cd\u65b9\u5f0f\u7684\u5f0a\u7aef\u662f\u5b83\u628a\u6570\u636e\u5e93\u4e2d\u539f\u6709\u7684\u6570\u636e\u90fd\u9500\u6bc1\u4e86\u3002<\/p>\n
            \u4e3a\u4e86\u89e3\u51b3\u8fd9\u79cd\u66f4\u65b0\u6a21\u578b\u5bfc\u81f4\u5220\u9664\u6389\u539f\u6765\u7684\u6570\u636e\u7684\u5f0a\u7aef\u3002\u4e0b\u4e00\u7ae0\u5c06\u4f1a\u4ecb\u7ecd\u4e00\u79cd\u66f4\u597d\u7684\u65b9\u5f0f\u7528\u4e8e\u66f4\u65b0\u6570\u636e\u5e93\u3002<\/p>\n
            \"\"<\/div><\/p>\n
            3.3 \u6570\u636e\u5e93\u64cd\u4f5c<\/h2>\n
            \"\"<\/div><\/p>\n
            3.3.1 \u589e<\/h3>\n
            \u6a21\u578b\u8868  \u6620\u5c04\u5230\u6570\u636e\u4e2d<\/strong><\/p>\n
            class School(db.Model):\n    __tablename__ = "school"\n    id = db.Column(db.Integer,primary_key=True,nullable=False,autoincrement=True,comment="ID")\n    name = db.Column(db.String(30),nullable=False,server_default='',comment="\u5b66\u6821\u540d\u79f0")\n    area = db.Column(db.String(30),nullable=False,server_default='',comment="\u6240\u5c5e\u5730\u533a")\n    score = db.Column(db.Integer,nullable=False,server_default='600',comment="\u5f55\u53d6\u5206\u6570\u7ebf")\n    def __repr__(self):\n        return "<School(name:{})>".format(self.name)\n\ndb.create_all()<\/code><\/pre>\n
            \u5b9e\u4f8b3.3.1.1: \u65b0\u589e\u5b9e\u4f8b<\/strong><\/h4>\n
            \u65b0\u589e\u56db\u6761\u8bb0\u5f55\u6620\u5c04\u5230\u6570\u636e\u5e93\u4e2d<\/strong><\/p>\n
            school_01 =School(name="\u5317\u4eac\u5927\u5b66",area="\u5317\u4eac",score=658)  # \u5b9e\u4f8b\u5316\u6a21\u578b\u7c7b\u4f5c\u4e3a\u4e00\u6761\u8bb0\u5f55\nschool_02 =School(name="\u6e05\u534e\u5927\u5b66",area="\u5317\u4eac",score=667)\nschool_03 =School(name="\u4e2d\u5c71\u5927\u5b66",area="\u5e7f\u4e1c",score=645)\nschool_04 =School(name="\u590d\u65e6\u5927\u5b66",area="\u4e0a\u6d77",score=650)\n\ndb.session.add(school_01)   # \u628a\u65b0\u521b\u5efa\u7684\u8bb0\u5f55\u6dfb\u52a0\u5230\u6570\u636e\u5e93\u4f1a\u8bdd\ndb.session.add(school_02)\ndb.session.add(school_03)\ndb.session.add(school_04)\n\ndb.session.commit()  # \u63d0\u4ea4\u6570\u636e\u5e93\u4f1a\u8bdd<\/code><\/pre>\n
            \u63d0\u793a\uff1a\u6570\u636e\u5e93\u4f1a\u8bdddb.session\u548c\u540e\u9762\u4ecb\u7ecd\u7684Flasksession\u5bf9\u8c61\u6ca1\u6709\u5173\u7cfb\u3002db.session\u662f\u6570\u636e\u5e93\u4f1a\u8bdd\u4e5f\u79f0\u4e3a\u4e8b\u52a1\u3002<\/em><\/p>\n
              \n
            1. \u5b9e\u4f8b\u5316\u6a21\u578b\u7c7b\u521b\u5efa\u5bf9\u8c61\uff0c\u8be5\u5bf9\u8c61\u4f5c\u4e3a\u4e00\u6761\u8bb0\u5f55\uff0c\u5b9e\u4f8b\u5316\u7684\u8fc7\u7a0b\u4f20\u5165\u7684\u53c2\u6570\u4e3a\u5b57\u6bb5\u5185\u5bb9\u3002<\/li>\n
            2. \u628a\u65b0\u521b\u5efa\u7684\u8bb0\u5f55\u6dfb\u52a0\u5230\u6570\u636e\u5e93\u4f1a\u8bdd\u3002<\/li>\n
            3. \u63d0\u4ea4\u6570\u636e\u5e93\u4f1a\u8bdd<\/li>\n<\/ol>\n
              \u67e5\u770b\u6570\u636e\u5e93<\/strong><\/p>\n
              \"\"<\/div><\/p>\n
              \u63d0\u793a1 \uff1a\u5982\u679cadd\u591a\u6761\u8bb0\u5f55\u53ef\u4ee5\u4f7f\u7528add_all()\u4e00\u6b21\u6dfb\u52a0\u5305\u542b\u591a\u6761\u8bb0\u5f55\u7684\u5217\u8868<\/em><\/p>\n
              \u5982\uff1adb.session.add_all([school_01,school_02,school_03\uff0cschool_04])<\/code><\/em><\/p>\n
              3.3.2 \u67e5<\/h3>\n
              \"\"<\/div><\/p>\n
              \u5728\u6211\u4eec\u7684flask\u4e2ddb.session\u51fa\u7684\u5bf9\u8c61\u8c03\u7528query<\/code>\u5c5e\u6027\uff0c\u53ef\u4ee5\u901a\u8fc7query\u5c5e\u6027\u8c03\u7528\u5404\u79cd\u8fc7\u6ee4\u65b9\u6cd5\u5b8c\u6210\u67e5\u8be2\u3002<\/p>\n
              \u6a21\u578b\u7c7b.<\u8fc7\u6ee4\u65b9\u6cd5>.<\u67e5\u8be2\u65b9\u6cd5><\/code><\/pre>\n
              \u5e38\u7528\u8fc7\u6ee4\u5668\u8868\uff1a<\/strong><\/p>\n\n\n\n\n\n\n\n\n\n\n
              \u8fc7\u6ee4\u5668<\/th>\n\u8bf4\u660e<\/th>\n<\/tr>\n<\/thead>\n
              filter()<\/td>\n\u4f7f\u7528\u6307\u5b9a\u7684\u89c4\u5219\u8fc7\u6ee4\u8bb0\u5f55\u76f8\u5f53\u4e8esql\u7684where\u7ea6\u675f\u6761\u4ef6\uff0c\u8fd4\u56de\u4e00\u4e2a\u65b0\u67e5\u8be2<\/td>\n<\/tr>\n
              filter_by()<\/td>\n\u540cfilter\u539f\u7406\uff0c\u4e0d\u540c\u7684\u662f\u67e5\u8be2\u7684\u65f6\u8981\u4f7f\u7528\u5173\u952e\u5b57\u53c2\u6570\uff0c\u8fd4\u56de\u4e00\u4e2a\u65b0\u67e5\u8be2<\/td>\n<\/tr>\n
              limit()<\/td>\n\u4f7f\u7528\u6307\u5b9a\u7684\u503c\u9650\u5236\u539f\u67e5\u8be2\u8fd4\u56de\u7684\u7ed3\u679c\u7684\u6570\u91cf\uff0c\u8fd4\u56de\u4e00\u4e2a\u65b0\u67e5\u8be2<\/td>\n<\/tr>\n
              offset()<\/td>\n\u504f\u79fb\u539f\u67e5\u8be2\u8fd4\u56de\u7684\u7ed3\u679c\uff0c\u8fd4\u56de\u4e00\u4e2a\u65b0\u67e5\u8be2<\/td>\n<\/tr>\n
              order_by()<\/td>\n\u6839\u636e\u6307\u5b9a\u6761\u4ef6\u5bf9\u539f\u67e5\u8be2\u7ed3\u6784\u8fdb\u884c\u6392\u5e8f\uff0c\u8fd4\u56de\u4e00\u4e2a\u65b0\u67e5\u8be2<\/td>\n<\/tr>\n
              group_by()<\/td>\n\u6839\u636e\u6307\u5b9a\u6761\u4ef6\u5bf9\u539f\u6765\u67e5\u8be2\u7ed3\u6784\u8fdb\u884c\u5206\u7ec4\uff0c\u8fd4\u56de\u4e00\u4e2a\u65b0\u67e5\u8be2<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
              \u5b9e\u4f8b3.3.2.1: \u67e5\u8be2\u5b9e\u4f8b<\/strong><\/h4>\n
              \u4e0b\u9762\u51e0\u4e2a\u67e5\u8be2\u6848\u4f8b\u9700\u8981\u5728\u5b9e\u4f8b3.3.1<\/code>\u5b8c\u6210\u7684\u57fa\u7840\u4e0a\u64cd\u4f5c<\/em><\/p>\n
              all()\u8fd4\u56de\u4e00\u4e2a\u5217\u8868\uff0c\u5217\u8868\u91cc\u5b58\u653e\u6240\u6709\u7b26\u5408\u6761\u4ef6\u7684\u8bb0\u5f55<\/strong><\/p>\n
              all_school = School.query.all()\nprint(all_school) \n\n# \u8f93\u51fa\uff1a[<School(name:\u5317\u4eac\u5927\u5b66)>, <School(name:\u6e05\u534e\u5927\u5b66)>, <School(name:\u4e2d\u5c71\u5927\u5b66)>, <School(name:\u590d\u65e6\u5927\u5b66)>]<\/code><\/pre>\n
              first()\u8fd4\u56de\u7b26\u5408\u6761\u4ef6\u7684\u7b2c\u4e00\u6761\u8bb0\u5f55\uff1a<\/strong><\/p>\n
              school_01 =School.query.first()\nprint(school_01)\n\n# \u8f93\u51fa\uff1a<School(name:\u5317\u4eac\u5927\u5b66)><\/code><\/pre>\n
              get()\u8fd4\u56de\u6307\u5b9a\u4e3b\u952e\u503c\uff08id\u5b57\u6bb5\uff09\u7684\u8bb0\u5f55\uff1a<\/strong><\/p>\n
              school_01 = School.query.get(1)\nprint(school_01)\n\n#\u8f93\u51fa\uff1a<School(name:\u5317\u4eac\u5927\u5b66)><\/code><\/pre>\n
              filter() \u4f7f\u7528\u6307\u5b9a\u7684\u89c4\u5219\u8fc7\u6ee4\u8bb0\u5f55\u76f8\u5f53\u4e8esql\u7684where\u7ea6\u675f\u6761\u4ef6\uff0c\u8fd4\u56de\u65b0\u4ea7\u751f\u7684\u67e5\u8be2\u5bf9\u8c61\u3002<\/strong><\/p>\n
              beijing_all = School.query.filter(School.area == "\u5317\u4eac").all()\nbeijing_first = School.query.filter(School.area == "\u5317\u4eac").first()\nprint(beijing_all)\nprint(beijing_first)\n\n# \u8f93\u51fa\uff1a[<School(name:\u5317\u4eac\u5927\u5b66)>, <School(name:\u6e05\u534e\u5927\u5b66)>]\n#       <School(name:\u5317\u4eac\u5927\u5b66)><\/code><\/pre>\n
              filter_by\uff1a\u540cfilter()\u6548\u679c\u4e00\u6837\uff0c\u67e5\u8be2\u7684\u65f6\u5019\u4f7f\u7528\u5173\u952e\u5b57\u53c2\u6570\u67e5\u8be2\uff08\u65e0\u6cd5\u8fdb\u884c\u591a\u8868\u590d\u6742\u67e5\u8be2\uff0c\u4e0d\u63a8\u8350\u4f7f\u7528\uff09<\/strong><\/p>\n
              zhongshan_school = School.query.filter_by(name='\u4e2d\u5c71\u5927\u5b66').all()\nprint(zhongshan_school)\n\n# \u8f93\u51fa\uff1a[<School(name:\u4e2d\u5c71\u5927\u5b66)>]<\/code><\/pre>\n
              db.session.qury(\u6a21\u578b\u7c7b)<\/code>\u7b49\u4ef7\u4e8e\u6a21\u578b\u7c7b.query<\/code>\uff0cdb.session.qury\u529f\u80fd\u66f4\u5f3a\u5927\u4e00\u4e9b\uff0c\u53ef\u4ee5\u8fdb\u884c\u591a\u8868\u67e5\u8be2\u3002<\/strong><\/p>\n
              fudan_school = School.query.filter(School.name == '\u590d\u65e6\u5927\u5b66').first()\nprint(fudan_school)  \n# \u8f93\u51fa\uff1a<School(name:\u590d\u65e6\u5927\u5b66)>\n\nfudan_school = db.session.query(School).filter(School.name == '\u590d\u65e6\u5927\u5b66').first()\nprint(fudan_school)\n# \u8f93\u51fa\uff1a<School(name:\u590d\u65e6\u5927\u5b66)><\/code><\/pre>\n
              \u63d0\u793a\uff1a\u5176\u4ed6\u7684\u8fc7\u6ee4\u5668\u4f1a\u5728\u63a5\u4e0b\u6765\u7684\u7ae0\u8282\u5177\u4f53\u6839\u636e\u5b9e\u9645\u6848\u4f8b\u8bb2\u89e3<\/em><\/p>\n
              3.3.3 \u6539<\/h3>\n
              \u5b9e\u4f8b3.3.3.1: \u4fee\u6539\u5b9e\u4f8b<\/strong><\/h4>\n
              \u4fee\u6539\u5317\u4eac\u5927\u5b66\u7684\u5f55\u53d6\u6210\u7ee9<\/strong><\/p>\n
              beida = School.query.filter(School.name=='\u5317\u4eac\u5927\u5b66').first()\nbeida.score = 630\ndb.session.commit()<\/code><\/pre>\n
              \"\"<\/div><\/p>\n
              \u66f4\u65b0\u4e00\u6761\u8bb0\u5f55\u5206\u4e3a\u4e00\u4e0b\u51e0\u90e8\uff1a<\/p>\n
                \n
              1. \n
                \u627e\u5230\u5bf9\u5e94\u7684\u8bb0\u5f55\u5bf9\u8c61<\/p>\n<\/li>\n
              2. \n
                \u4fee\u6539\u8bb0\u5f55\u5bf9\u8c61\u7684\u5c5e\u6027<\/p>\n<\/li>\n
              3. \n
                \u76f4\u63a5\u8c03\u7528db.session.commit()<\/code>\u63d0\u4ea4\u4f1a\u8bdd<\/p>\n
                \u63d0\u793a\uff1a\u53ea\u6709\u8981\u63d2\u5165\u65b0\u7684\u8bb0\u5f55\u6216\u8981\u5c06\u73b0\u6709\u7684\u8bb0\u5f55\u6dfb\u52a0\u5230\u4f1a\u8bdd\u4e2d\u65f6\u624d\u9700\u8981\u4f7f\u7528add\uff08\uff09\u65b9\u6cd5\u3002\u53ea\u662f\u66f4\u65b0\u73b0\u6709\u8bb0\u5f55\u7684\u65f6\u53ef\u4ee5\u4fee\u6539\u8bb0\u5f55\u5bf9\u8c61\u5c5e\u6027\u540e\u76f4\u63a5\u63d0\u4ea4\u4f1a\u8bdd<\/em><\/p>\n<\/li>\n<\/ol>\n
                3.3.4 \u5220<\/h3>\n
                \"\"<\/div><\/p>\n
                \u5b9e\u4f8b3.3.4.1: \u5220\u9664\u5b9e\u4f8b<\/strong><\/h4>\n
                \u4ece\u6570\u636e\u5e93\u4e2d\u5220\u9664\u6e05\u534e\u5927\u5b66\u76f8\u5173\u4fe1\u606f<\/strong><\/p>\n
                qinghua = School.query.filter(School.name=='\u6e05\u534e\u5927\u5b66').first()\ndb.session.delete(qinghua)\ndb.session.commit()<\/code><\/pre>\n
                \"\"<\/div><\/p>\n
                \u5220\u9664\u4e00\u6761\u8bb0\u5f55\u5206\u4e3a\u4ee5\u4e0b\u51e0\u6b65\uff1a<\/p>\n
                  \n
                1. \u627e\u5230\u5bf9\u5e94\u7684\u8bb0\u5f55\u5bf9\u8c61<\/li>\n
                2. \u9700\u8981\u8c03\u7528delete()<\/code>\u65b9\u6cd5\u5728\u4f1a\u8bdd\u4e2d\u6807\u8bc6\u9700\u8981\u5220\u9664\u7684\u8bb0\u5f55\uff0c\u5177\u4f53\u662f\u628a\u8be5\u8bb0\u5f55\u5bf9\u8c61\u4f20\u5165db.session.delete(\u8bb0\u5f55\u5bf9\u8c61)<\/code>\u5b9e\u73b0\u6807\u8bc6\u3002<\/li>\n
                3. \u8c03\u7528db.session.commit()<\/code>\u63d0\u4ea4\u4f1a\u8bdd\u3002<\/li>\n<\/ol>\n
                  \"\"<\/div><\/p>\n","protected":false},"excerpt":{"rendered":"
                  05-\u6570\u636e\u5e93 \u6570\u636e\u5e93\uff0c\u987e\u540d\u601d\u4e49\u662f\u50a8\u5b58\u6570\u636e\u7684\u4ed3\u5e93\uff0c\u5e38\u89c1\u7684\u7ba1\u7406\u6570\u636e\u5e93\u7684\u8f6f\u4ef6\u88ab\u79f0\u4e3a\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\uff08DBMS, Dat […]<\/p>\n","protected":false},"author":3,"featured_media":2607,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[269],"tags":[273],"_links":{"self":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/2134"}],"collection":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2134"}],"version-history":[{"count":0,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/2134\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/media\/2607"}],"wp:attachment":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2134"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2134"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2134"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}