\u200b \u6211\u4eec\u5728\u4f7f\u7528Django\u6846\u67b6\u5f00\u53d1web\u5e94\u7528\u7684\u8fc7\u7a0b\u4e2d\uff0c\u4e0d\u53ef\u907f\u514d\u5730\u4f1a\u6d89\u53ca\u5230\u6570\u636e\u7684\u7ba1\u7406\u64cd\u4f5c\uff08\u589e\u3001\u5220\u3001\u6539\u3001\u67e5\uff09\uff0c\u800c\u4e00\u65e6\u8c08\u5230\u6570\u636e\u7684\u7ba1\u7406\u64cd\u4f5c\uff0c\u5c31\u9700\u8981\u7528\u5230\u6570\u636e\u5e93\u7ba1\u7406\u8f6f\u4ef6\uff0c\u4f8b\u5982mysql\u3001oracle\u3001Microsoft SQL Server\u7b49\u3002<\/p>\n\n\n\n
\u5982\u679c\u5e94\u7528\u7a0b\u5e8f\u9700\u8981\u64cd\u4f5c\u6570\u636e\uff08\u6bd4\u5982\u5c06\u7528\u6237\u6ce8\u518c\u4fe1\u606f\u6c38\u4e45\u5b58\u653e\u8d77\u6765\uff09\uff0c\u90a3\u4e48\u6211\u4eec\u9700\u8981\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7f16\u5199\u539f\u751fsql\u8bed\u53e5\uff0c\u7136\u540e\u4f7f\u7528pymysql\u6a21\u5757\u8fdc\u7a0b\u64cd\u4f5cmysql\u6570\u636e\u5e93<\/p>\n\n\n\n
\u9488\u5bf9\u5e94\u7528\u7a0b\u5e8f\u7684\u6570\u636e\u64cd\u4f5c\uff0c\u76f4\u63a5\u7f16\u5199\u539f\u751fsql\u8bed\u53e5\u4f1a\u5b58\u5728\u4e24\u65b9\u9762\u7684\u95ee\u9898\uff0c\u4e25\u91cd\u5f71\u54cd\u5f00\u53d1\u6548\u7387\uff0c\u5982\u4e0b<\/p>\n\n\n\n
#1. sql\u8bed\u53e5\u7684\u6267\u884c\u6548\u7387\u95ee\u9898\uff1a\u5e94\u7528\u5f00\u53d1\u7a0b\u5e8f\u5458\u9700\u8981\u8017\u8d39\u4e00\u5927\u90e8\u5206\u7cbe\u529b\u53bb\u4f18\u5316sql\u8bed\u53e5<\/em>\n#2. \u6570\u636e\u5e93\u8fc1\u79fb\u95ee\u9898\uff1a\u9488\u5bf9mysql\u5f00\u53d1\u7684sql\u8bed\u53e5\u65e0\u6cd5\u76f4\u63a5\u5e94\u7528\u5230oracle\u6570\u636e\u5e93\u4e0a\uff0c\u4e00\u65e6\u9700\u8981\u8fc1\u79fb\u6570\u636e\u5e93\uff0c\u4fbf\u9700\u8981\u8003\u8651\u8de8\u5e73\u53f0\u95ee\u9898<\/em>\n\n\u4e3a\u4e86\u89e3\u51b3\u4e0a\u8ff0\u95ee\u9898\uff0cdjango\u5f15\u5165\u4e86ORM\u7684\u6982\u5ff5\uff0cORM\u5168\u79f0Object Relational Mapping\uff0c\u5373\u5bf9\u8c61\u5173\u7cfb\u6620\u5c04\uff0c\u662f\u5728pymysq\u4e4b\u4e0a\u53c8\u8fdb\u884c\u4e86\u4e00\u5c42\u5c01\u88c5\uff0c\u5bf9\u4e8e\u6570\u636e\u7684\u64cd\u4f5c\uff0c\u6211\u4eec\u65e0\u9700\u518d\u53bb\u7f16\u5199\u539f\u751fsql\uff0c\u53d6\u4ee3\u4ee3\u4e4b\u7684\u662f\u57fa\u4e8e\u9762\u5411\u5bf9\u8c61\u7684\u601d\u60f3\u53bb\u7f16\u5199\u7c7b\u3001\u5bf9\u8c61\u3001\u8c03\u7528\u76f8\u5e94\u7684\u65b9\u6cd5\u7b49\uff0cORM\u4f1a\u5c06\u5176\u8f6c\u6362\/\u6620\u5c04\u6210\u539f\u751fSQL\u7136\u540e\u4ea4\u7ed9pymysql\u6267\u884c\n\n\u200b \u6709\u4e86ORM\u6846\u67b6\uff0c\u5f00\u53d1\u4eba\u5458\u65e2\u4e0d\u7528\u518d\u53bb\u8003\u8651\u539f\u751fSQL\u7684\u4f18\u5316\u95ee\u9898\uff0c\u4e5f\u4e0d\u7528\u8003\u8651\u6570\u636e\u5e93\u8fc1\u79fb\u7684\u95ee\u9898\uff0cORM\u90fd\u5e2e\u6211\u4eec\u505a\u4e86\u4f18\u5316\u4e14\u652f\u6301\u591a\u79cd\u6570\u636e\u5e93\uff0c\u8fd9\u6781\u5927\u5730\u63d0\u5347\u4e86\u6211\u4eec\u7684\u5f00\u53d1\u6548\u7387\n\n\u5982\u4f55\u4f7f\u7528\uff1a\n1\u3001\u6570\u636e\u6765\u6e90\u4e8e\u6570\u636e\u5e93\u7684\u8868\uff0c\u800cORM\u7684\u6a21\u578b\u7c7b\u5bf9\u5e94\u6570\u636e\u5e93\u8868\uff0c\u6240\u4ee5\u82e5\u6211\u4eec\u60f3\u64cd\u4f5c\u6570\u636e\uff0c\u5fc5\u987b\u5148\u521b\u5efa\u6a21\u578b\u3002\n2\u3001\u518d\u6ce8\u518c\u5230\u5e94\u7528\n3\u3001\u518d\u914d\u7f6e\u6570\u636e\u5e93\u8fde\u63a5\n\u4ee5\u4e0b\u662f\u4e00\u4e2a mysql\u7684\u6570\u636e\u5e93\u8fde\u63a5\u914d\u7f6e\uff0c\u5305\u542b\u7528\u7684pymysql\u5e93\uff0c\u7528\u6237\u540dzwq\uff0c\u5bc6\u78015dc580\uff0c\u670d\u52a1\u5668zxz.xtaa.cn\uff0c\u6570\u636e\u5e93\u540ddouy\napp.config['SQLALCHEMY_DATABASE_URI'] = \"mysql+pymysql:\/\/zwq:5dc580@zxz.xtaa.cn\/douyin?charset=utf8\"\n\n\n\n\n\n\n\nFlask\u662f\u4e00\u4e2a\u8f7b\u91cf\u7ea7\u7684Web\u6846\u67b6\uff0c\u5176\u4e2d\u96c6\u6210\u7684ORM\u5de5\u5177SQLAlchemy\uff0c\u4f7f\u5f97\u5728Python\u4e2d\u8fdb\u884c\u6570\u636e\u5e93\u64cd\u4f5c\u53d8\u5f97\u66f4\u52a0\u7b80\u5355\u3002\u5728Flask\u4e2d\uff0c\u4f7f\u7528ORM\u53ef\u4ee5\u901a\u8fc7\u4f7f\u7528db.session\u5bf9\u8c61\u8bbf\u95ee\u6570\u636e\u5e93\uff0c\u5c06\u64cd\u4f5c\u8f6c\u6362\u4e3aPython\u5bf9\u8c61\u7684\u65b9\u6cd5\u3002 \u5728ORM\u4e2d\u7684\u4e00\u4e2a\u6838\u5fc3\u6982\u5ff5\u662f\u5173\u7cfb\uff0c\u5373\u5bf9\u8c61\u4e4b\u95f4\u7684\u5173\u7cfb\u3002\u5728Flask\u4e2d\uff0c\u4f7f\u7528db.relationship\u6765\u521b\u5efa\u5173\u7cfb\u3002\u672c\u6587\u5c06\u901a\u8fc7\u51e0\u4e2a\u65b9\u9762\u8be6\u7ec6\u4ecb\u7ecddb.relationship\u7684\u4f7f\u7528\u3002\n\u4e00\u3001\u521b\u5efa\u4e00\u5bf9\u591a\u5173\u7cfb\n\u5728ORM\u4e2d\uff0c\u4e00\u5bf9\u591a\u5173\u7cfb\u662f\u6307\u4e00\u4e2a\u5bf9\u8c61\uff08\u5982\u4e00\u4e2a\u7528\u6237\uff09\u53ef\u4ee5\u6709\u591a\u4e2a\u5b50\u5bf9\u8c61\uff08\u5982\u591a\u4e2a\u8ba2\u5355\uff09\u3002\u5728Flask\u4e2d\uff0c\u53ef\u4ee5\u901a\u8fc7db.relationship\u548cbackref\u53c2\u6570\u6765\u5b9a\u4e49\u4e00\u5bf9\u591a\u5173\u7cfb\u3002\u5728\u8fd9\u79cd\u5173\u7cfb\u4e2d\uff0c\u4e00\u4e2a\u5bf9\u8c61\uff08\u5982User\uff09\u53ef\u4ee5\u6709\u591a\u4e2a\u5b50\u5bf9\u8c61\uff08\u5982Order\uff09\uff0c\u800c\u4e00\u4e2a\u5b50\u5bf9\u8c61\uff08\u5982Order\uff09\u53ea\u80fd\u5f52\u5c5e\u4e8e\u4e00\u4e2a\u5bf9\u8c61\uff08\u5982User\uff09\u3002\n\n<\/code><\/pre>\n\n\n\n class User(db.Model):\n id = db.Column(db.Integer, primary_key=True)\n name = db.Column(db.String(50))\n orders = db.relationship(\"Order\", backref=\"user\")\n\n class Order(db.Model):\n id = db.Column(db.Integer, primary_key=True)\n total_price = db.Column(db.Float)\n user_id = db.Column(db.Integer, db.ForeignKey(\"user.id\"))\n\n user = User.query.first()\n orders = user.orders\n for order in orders:\n print(order.total_price)<\/code><\/pre>\n\n\n\n\u5728\u8fd9\u4e2a\u793a\u4f8b\u4e2d\uff0cUser\u548cOrder\u6a21\u578b\u4e4b\u95f4\u5efa\u7acb\u4e86\u4e00\u5bf9\u591a\u5173\u7cfb\u3002User\u6a21\u578b\u4e2d\u901a\u8fc7db.relationship\u5b9a\u4e49\u4e86\u4e00\u4e2a\u540d\u4e3aorders\u7684\u5c5e\u6027\u3002\u5728Order\u6a21\u578b\u4e2d\u901a\u8fc7user_id\u5217\u7684\u5916\u952e\u6765\u5173\u8054User\u6a21\u578b\u3002\u540c\u65f6\uff0cbackref\u53c2\u6570\u5b9a\u4e49\u4e86\u5b50\u5bf9\u8c61\u5982\u4f55\u8bbf\u95ee\u7236\u5bf9\u8c61\u3002\u5728\u8fd9\u4e2a\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7user.orders\u8bbf\u95ee\u8be5\u7528\u6237\u7684\u6240\u6709\u8ba2\u5355\uff0c\u5e76\u901a\u8fc7for\u5faa\u73af\u904d\u5386\u8ba2\u5355\u5bf9\u8c61\uff0c\u6253\u5370\u5176\u603b\u4ef7\u3002<\/p>\n\n\n\n
\u4e8c\u3001\u521b\u5efa\u591a\u5bf9\u591a\u5173\u7cfb<\/h2>\n\n\n\n
\u591a\u5bf9\u591a\u5173\u7cfb\u662f\u6307\u4e24\u4e2a\u5bf9\u8c61\u4e4b\u95f4\u76f8\u4e92\u5173\u8054\uff0c\u4e00\u4e2a\u5bf9\u8c61\u53ef\u4ee5\u6709\u591a\u4e2a\u5b50\u5bf9\u8c61\uff0c\u540c\u65f6\u4e00\u4e2a\u5b50\u5bf9\u8c61\u4e5f\u53ef\u4ee5\u5f52\u5c5e\u4e8e\u591a\u4e2a\u5bf9\u8c61\u3002\u5728Flask\u4e2d\uff0c\u53ef\u4ee5\u901a\u8fc7db.relationship\u548csecondary\u53c2\u6570\u6765\u5b9a\u4e49\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u5728\u8fd9\u79cd\u5173\u7cfb\u4e2d\u9700\u8981\u521b\u5efa\u4e00\u4e2a\u5173\u8054\u8868\uff0c\u7528\u6765\u4fdd\u5b58\u591a\u5bf9\u591a\u7684\u5173\u7cfb\u3002<\/p>\n\n\n\n
association_table = db.Table(\n 'association', db.Model.metadata,\n db.Column('user_id', db.Integer, db.ForeignKey('user.id')),\n db.Column('project_id', db.Integer, db.ForeignKey('project.id')))\n\n class User(db.Model):\n id = db.Column(db.Integer, primary_key=True)\n name = db.Column(db.String(50))\n projects = db.relationship(\"Project\", secondary=association_table, backref=\"users\")\n\n class Project(db.Model):\n id = db.Column(db.Integer, primary_key=True)\n name = db.Column(db.String(50))\n\n user = User.query.first()\n projects = user.projects\n for project in projects:\n print(project.name)<\/code><\/pre>\n\n\n\n\u5728\u8fd9\u4e2a\u793a\u4f8b\u4e2d\uff0cUser\u548cProject\u6a21\u578b\u4e4b\u95f4\u5efa\u7acb\u4e86\u591a\u5bf9\u591a\u5173\u7cfb\u3002User\u6a21\u578b\u4e2d\u5b9a\u4e49\u4e86\u540d\u4e3aprojects\u7684\u5c5e\u6027\u3002\u5728Project\u6a21\u578b\u4e2d\u540c\u6837\u5b9a\u4e49\u4e86\u540d\u4e3ausers\u7684\u5c5e\u6027\u6765\u53cd\u5411\u8bbf\u95ee\u7236\u5bf9\u8c61\u3002\u5173\u8054\u8868association_table\u901a\u8fc7db.Table\u6765\u521b\u5efa\u3002\u5728User\u6a21\u578b\u4e2d\u901a\u8fc7secondary\u53c2\u6570\u6765\u6307\u5b9a\u5173\u8054\u8868\u3002\u5728\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7user.projects\u8bbf\u95ee\u8be5\u7528\u6237\u6240\u53c2\u4e0e\u7684\u6240\u6709\u9879\u76ee\uff0c\u5e76\u901a\u8fc7for\u5faa\u73af\u904d\u5386\u6253\u5370\u6bcf\u4e2a\u9879\u76ee\u7684\u540d\u5b57\u3002<\/p>\n\n\n\n
\u4e09\u3001\u5b9a\u4e49\u5173\u7cfb\u5c5e\u6027\u7684\u9650\u5236<\/h2>\n\n\n\n
\u5728ORM\u4e2d\uff0c\u8fd8\u53ef\u4ee5\u4e3a\u5173\u7cfb\u5c5e\u6027\u5b9a\u4e49\u4e00\u4e9b\u9650\u5236\uff0c\u5982elenment_order\u3001primaryjoin\u3001secondaryjoin\u7b49\u7b49\u3002\u8fd9\u4e9b\u9650\u5236\u53ef\u4ee5\u5e2e\u52a9\u6211\u4eec\u66f4\u597d\u5730\u63a7\u5236\u6211\u4eec\u7684\u5173\u7cfb\u3002\u4f8b\u5982\uff0c\u4e3a\u4e86\u63a7\u5236\u67e5\u8be2\u7ed3\u679c\uff0c\u6211\u4eec\u53ef\u4ee5\u6dfb\u52a0primaryjoin\u53c2\u6570<\/p>\n\n\n\n
\u56db\u3001\u4f7f\u7528back_populates\u6765\u53cd\u5411\u5f15\u7528\u4e00\u5bf9\u591a\u5173\u7cfb<\/h2>\n\n\n\n
\u5728Flask\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528back_populates\u6765\u53cd\u5411\u5f15\u7528\u4e00\u5bf9\u591a\u5173\u7cfb\u3002\u8fd9\u79cd\u65b9\u5f0f\u53ef\u4ee5\u5e2e\u52a9\u6211\u4eec\u66f4\u597d\u5730\u63a7\u5236\u5173\u7cfb\uff0c\u5e76\u907f\u514d\u5faa\u73af\u5f15\u7528<\/p>\n","protected":false},"excerpt":{"rendered":"
\u4e00 ORM\u662f\u4ec0\u4e48\uff1f\u4e3a\u4f55\u8981\u6709ORM\uff1f \u200b \u6211\u4eec\u5728\u4f7f\u7528Django\u6846\u67b6\u5f00\u53d1web\u5e94\u7528\u7684\u8fc7\u7a0b\u4e2d\uff0c\u4e0d\u53ef\u907f\u514d\u5730\u4f1a\u6d89\u53ca\u5230\u6570 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[],"class_list":["post-1634","post","type-post","status-publish","format-standard","hentry","category-10"],"_links":{"self":[{"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/posts\/1634","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/comments?post=1634"}],"version-history":[{"count":0,"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/posts\/1634\/revisions"}],"wp:attachment":[{"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/media?parent=1634"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/categories?post=1634"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/blog.xtaa.cn\/index.php\/wp-json\/wp\/v2\/tags?post=1634"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}