{"id":2348,"date":"2025-03-04T19:24:15","date_gmt":"2025-03-04T11:24:15","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=2348"},"modified":"2025-03-04T19:24:15","modified_gmt":"2025-03-04T11:24:15","slug":"sqlite-%e7%ba%a6%e6%9d%9f","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/03\/04\/sqlite-%e7%ba%a6%e6%9d%9f\/","title":{"rendered":"SQLite \u7ea6\u675f"},"content":{"rendered":"\n

\u5728 SQLite \u4e2d\uff0c\u7ea6\u675f\uff08Constraint\uff09<\/strong>\u7528\u4e8e\u786e\u4fdd\u6570\u636e\u5e93\u4e2d\u7684\u6570\u636e\u5b8c\u6574\u6027\u548c\u4e00\u81f4\u6027\u3002SQLite \u652f\u6301\u591a\u79cd\u7ea6\u675f\u7c7b\u578b\uff0c\u5e38\u89c1\u7684\u7ea6\u675f\u5305\u62ec NOT NULL<\/code>\u3001UNIQUE<\/code>\u3001PRIMARY KEY<\/code>\u3001FOREIGN KEY<\/code>\u3001CHECK<\/code> \u548c DEFAULT<\/code>\u3002<\/p>\n\n\n\n

\n\n\n\n

1. SQLite \u7ea6\u675f\u7c7b\u578b<\/h2>\n\n\n\n

1.1 NOT NULL<\/code> \u7ea6\u675f<\/h3>\n\n\n\n
    \n
  • \u786e\u4fdd\u67d0\u4e2a\u5b57\u6bb5\u4e0d\u80fd\u4e3a\u7a7a\u3002<\/li>\n\n\n\n
  • \u9002\u7528\u4e8e INSERT<\/code> \u6216 UPDATE<\/code> \u64cd\u4f5c\uff0c\u82e5\u672a\u63d0\u4f9b\u503c\u6216\u63d0\u4f9b NULL<\/code>\uff0c\u4f1a\u62a5\u9519\u3002<\/li>\n<\/ul>\n\n\n\n

    \u793a\u4f8b\uff1a<\/h4>\n\n\n\n
    CREATE TABLE users (\n    id INTEGER PRIMARY KEY,\n    name TEXT NOT NULL,\n    email TEXT\n);<\/code><\/pre>\n\n\n\n
      \n
    • name<\/code> \u5217\u5fc5\u987b\u6709\u503c\uff0c\u5426\u5219\u63d2\u5165\u6570\u636e\u65f6\u4f1a\u5931\u8d25\u3002<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n
      1.2 UNIQUE<\/code> \u7ea6\u675f<\/h3>\n\n\n\n
        \n
      • \u786e\u4fdd\u67d0\u5217\u7684\u503c\u5728\u8868\u4e2d\u662f\u552f\u4e00\u7684\u3002<\/li>\n\n\n\n
      • \u53ef\u4ee5\u7528\u4e8e\u5355\u5217\u6216\u591a\u5217\u7ec4\u5408\u3002<\/li>\n<\/ul>\n\n\n\n
        \u793a\u4f8b\uff1a<\/h4>\n\n\n\n
        CREATE TABLE users (\n    id INTEGER PRIMARY KEY,\n    email TEXT UNIQUE\n);<\/code><\/pre>\n\n\n\n
          \n
        • email<\/code> \u5217\u7684\u503c\u4e0d\u80fd\u91cd\u590d\u3002<\/li>\n<\/ul>\n\n\n\n
          \u591a\u5217\u7ec4\u5408 UNIQUE<\/code><\/h4>\n\n\n\n
          CREATE TABLE orders (\n    order_id INTEGER,\n    product_id INTEGER,\n    quantity INTEGER,\n    UNIQUE(order_id, product_id)\n);<\/code><\/pre>\n\n\n\n
            \n
          • \u8fd9\u610f\u5473\u7740 (order_id, product_id)<\/code> \u7ec4\u5408\u5fc5\u987b\u552f\u4e00\u3002<\/li>\n<\/ul>\n\n\n\n
            \n\n\n\n
            1.3 PRIMARY KEY<\/code>\uff08\u4e3b\u952e\uff09\u7ea6\u675f<\/h3>\n\n\n\n
              \n
            • \u4f5c\u7528\u7c7b\u4f3c\u4e8e UNIQUE<\/code>\uff0c\u4f46\u5fc5\u987b\u662f \u975e NULL<\/strong> \u4e14\u81ea\u52a8\u7d22\u5f15\u3002<\/li>\n\n\n\n
            • \u901a\u5e38\u7528\u4e8e\u552f\u4e00\u6807\u8bc6\u4e00\u884c\u6570\u636e\u3002<\/li>\n<\/ul>\n\n\n\n
              \u793a\u4f8b\uff1a<\/h4>\n\n\n\n
              CREATE TABLE users (\n    id INTEGER PRIMARY KEY, \n    name TEXT NOT NULL\n);<\/code><\/pre>\n\n\n\n
                \n
              • id<\/code> \u5217\u662f\u4e3b\u952e\uff0c\u6bcf\u884c\u7684 id<\/code> \u503c\u5fc5\u987b\u552f\u4e00\u4e14\u4e0d\u80fd\u4e3a\u7a7a\u3002<\/li>\n<\/ul>\n\n\n\n
                \u81ea\u52a8\u9012\u589e\u4e3b\u952e\uff08AUTOINCREMENT<\/code>\uff09<\/strong><\/p>\n\n\n\n
                CREATE TABLE users (\n    id INTEGER PRIMARY KEY AUTOINCREMENT, \n    name TEXT NOT NULL\n);<\/code><\/pre>\n\n\n\n
                  \n
                • id<\/code> \u5217\u4f1a\u81ea\u52a8\u9012\u589e\uff0c\u4f46 AUTOINCREMENT<\/code> \u53ef\u80fd\u5f71\u54cd\u6027\u80fd\uff0c\u56e0\u6b64\u4ec5\u5728\u9700\u8981\u4e25\u683c\u8fde\u7eed ID \u65f6\u4f7f\u7528\u3002<\/li>\n<\/ul>\n\n\n\n
                  \n\n\n\n
                  1.4 FOREIGN KEY<\/code>\uff08\u5916\u952e\uff09\u7ea6\u675f<\/h3>\n\n\n\n
                    \n
                  • \u7528\u4e8e\u5efa\u7acb\u8868\u4e4b\u95f4\u7684\u5173\u7cfb\uff0c\u786e\u4fdd\u6570\u636e\u4e00\u81f4\u6027\u3002<\/li>\n\n\n\n
                  • \u9700\u8981 PRAGMA foreign_keys = ON;<\/code> \u542f\u7528\u5916\u952e\u652f\u6301\u3002<\/li>\n<\/ul>\n\n\n\n
                    \u793a\u4f8b\uff1a<\/h4>\n\n\n\n
                    PRAGMA foreign_keys = ON;\n\nCREATE TABLE users (\n    id INTEGER PRIMARY KEY,\n    name TEXT NOT NULL\n);\n\nCREATE TABLE orders (\n    order_id INTEGER PRIMARY KEY,\n    user_id INTEGER,\n    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE\n);<\/code><\/pre>\n\n\n\n
                      \n
                    • orders.user_id<\/code> \u5fc5\u987b\u662f users.id<\/code> \u4e2d\u7684\u4e00\u4e2a\u503c\u3002<\/li>\n\n\n\n
                    • ON DELETE CASCADE<\/code> \u4f7f\u5f97\u5f53 users<\/code> \u8868\u4e2d\u7684 id<\/code> \u88ab\u5220\u9664\u65f6\uff0c\u76f8\u5173\u7684 orders<\/code> \u8bb0\u5f55\u4e5f\u4f1a\u88ab\u5220\u9664\u3002<\/li>\n<\/ul>\n\n\n\n
                      \n\n\n\n
                      1.5 CHECK<\/code> \u7ea6\u675f<\/h3>\n\n\n\n
                        \n
                      • \u7528\u4e8e\u9650\u5236\u5217\u7684\u53d6\u503c\u8303\u56f4\uff0c\u786e\u4fdd\u7b26\u5408\u6761\u4ef6\u3002<\/li>\n<\/ul>\n\n\n\n
                        \u793a\u4f8b\uff1a<\/h4>\n\n\n\n
                        CREATE TABLE products (\n    id INTEGER PRIMARY KEY,\n    price REAL CHECK (price > 0),\n    stock INTEGER CHECK (stock >= 0)\n);<\/code><\/pre>\n\n\n\n
                          \n
                        • price<\/code> \u5fc5\u987b\u5927\u4e8e 0\uff0cstock<\/code> \u4e0d\u80fd\u4e3a\u8d1f\u6570\uff0c\u5426\u5219\u63d2\u5165\/\u66f4\u65b0\u6570\u636e\u65f6\u4f1a\u62a5\u9519\u3002<\/li>\n<\/ul>\n\n\n\n
                          \n\n\n\n
                          1.6 DEFAULT<\/code> \u7ea6\u675f<\/h3>\n\n\n\n
                            \n
                          • \u8bbe\u5b9a\u9ed8\u8ba4\u503c\uff0c\u5982\u679c INSERT<\/code> \u8bed\u53e5\u672a\u63d0\u4f9b\u503c\uff0c\u5219\u4f7f\u7528\u9ed8\u8ba4\u503c\u3002<\/li>\n<\/ul>\n\n\n\n
                            \u793a\u4f8b\uff1a<\/h4>\n\n\n\n
                            CREATE TABLE users (\n    id INTEGER PRIMARY KEY,\n    name TEXT NOT NULL,\n    created_at DATETIME DEFAULT CURRENT_TIMESTAMP\n);<\/code><\/pre>\n\n\n\n
                              \n
                            • created_at<\/code> \u9ed8\u8ba4\u5b58\u50a8\u5f53\u524d\u65f6\u95f4\u3002<\/li>\n<\/ul>\n\n\n\n
                              \n\n\n\n
                              2. \u7ec4\u5408\u591a\u4e2a\u7ea6\u675f<\/h2>\n\n\n\n
                              \u53ef\u4ee5\u5728\u540c\u4e00\u5217\u4e0a\u4f7f\u7528\u591a\u4e2a\u7ea6\u675f\uff0c\u4f8b\u5982\uff1a<\/p>\n\n\n\n
                              CREATE TABLE employees (\n    id INTEGER PRIMARY KEY AUTOINCREMENT,\n    name TEXT NOT NULL,\n    email TEXT UNIQUE,\n    salary REAL CHECK (salary >= 3000) DEFAULT 3000\n);<\/code><\/pre>\n\n\n\n
                                \n
                              • id<\/code> \u662f\u4e3b\u952e\uff0c\u81ea\u52a8\u9012\u589e\uff1b<\/li>\n\n\n\n
                              • name<\/code> \u4e0d\u80fd\u4e3a\u7a7a\uff1b<\/li>\n\n\n\n
                              • email<\/code> \u5fc5\u987b\u552f\u4e00\uff1b<\/li>\n\n\n\n
                              • salary<\/code> \u4e0d\u80fd\u4f4e\u4e8e 3000\uff0c\u9ed8\u8ba4\u503c\u4e3a 3000\u3002<\/li>\n<\/ul>\n\n\n\n
                                \n\n\n\n
                                3. \u5220\u9664\u7ea6\u675f<\/h2>\n\n\n\n
                                SQLite \u4e0d\u652f\u6301<\/strong> \u76f4\u63a5\u5220\u9664\u5df2\u6709\u8868\u7684\u7ea6\u675f\u3002\u8981\u4fee\u6539\u7ea6\u675f\uff0c\u9700\u8981\uff1a<\/p>\n\n\n\n
                                  \n
                                1. \u521b\u5efa\u4e00\u4e2a\u65b0\u8868\uff08\u5305\u542b\u65b0\u7684\u7ea6\u675f\uff09\u3002<\/li>\n\n\n\n
                                2. \u590d\u5236\u6570\u636e\u5230\u65b0\u8868\u3002<\/li>\n\n\n\n
                                3. \u5220\u9664\u65e7\u8868\u3002<\/li>\n\n\n\n
                                4. \u91cd\u547d\u540d\u65b0\u8868\u3002<\/li>\n<\/ol>\n\n\n\n
                                  \u793a\u4f8b\uff1a<\/p>\n\n\n\n
                                  BEGIN TRANSACTION;\n\nCREATE TABLE new_users (\n    id INTEGER PRIMARY KEY,\n    name TEXT NOT NULL\n);\n\nINSERT INTO new_users SELECT id, name FROM users;\n\nDROP TABLE users;\n\nALTER TABLE new_users RENAME TO users;\n\nCOMMIT;<\/code><\/pre>\n\n\n\n
                                  \n\n\n\n
                                  4. \u7ed3\u8bba<\/h2>\n\n\n\n
                                    \n
                                  • SQLite \u63d0\u4f9b NOT NULL<\/code>\u3001UNIQUE<\/code>\u3001PRIMARY KEY<\/code>\u3001FOREIGN KEY<\/code>\u3001CHECK<\/code> \u548c DEFAULT<\/code> \u7b49\u7ea6\u675f\u6765\u4fdd\u8bc1\u6570\u636e\u5b8c\u6574\u6027\u3002<\/li>\n\n\n\n
                                  • \u4e0d\u80fd\u76f4\u63a5\u5220\u9664\u7ea6\u675f\uff0c\u53ea\u80fd\u901a\u8fc7\u91cd\u5efa\u8868\u7684\u65b9\u5f0f\u4fee\u6539\u7ea6\u675f\u3002<\/li>\n\n\n\n
                                  • \u4f7f\u7528 PRAGMA foreign_keys = ON;<\/code> \u4ee5\u786e\u4fdd\u5916\u952e\u7ea6\u675f\u751f\u6548\u3002<\/li>\n<\/ul>\n\n\n\n
                                    \u66f4\u591a\u8be6\u7ec6\u5185\u5bb9\u8bf7\u5173\u6ce8\u5176\u4ed6\u76f8\u5173\u6587\u7ae0\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
                                    \u5728 SQLite \u4e2d\uff0c\u7ea6\u675f\uff08Constraint\uff09\u7528\u4e8e\u786e\u4fdd\u6570\u636e\u5e93\u4e2d\u7684\u6570\u636e\u5b8c\u6574\u6027\u548c\u4e00\u81f4\u6027\u3002SQLite \u652f\u6301\u591a\u79cd […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[76],"tags":[],"class_list":["post-2348","post","type-post","status-publish","format-standard","hentry","category-sqlite"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2348","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=2348"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2348\/revisions"}],"predecessor-version":[{"id":2349,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2348\/revisions\/2349"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=2348"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=2348"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=2348"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}