{"id":187462,"date":"2024-11-11T14:28:20","date_gmt":"2024-11-11T06:28:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/187462\/"},"modified":"2024-11-11T14:28:21","modified_gmt":"2024-11-11T06:28:21","slug":"%e6%95%b8%e6%93%9a%e5%ba%ab%e6%96%b0%e5%a2%9efk%e5%a4%96%e9%8d%b5%e7%9a%84%e6%ad%a5%e9%a9%9f%e8%a9%b3%e8%a7%a3-%e6%95%b8%e6%93%9a%e5%ba%ab%e7%9a%84%e5%a6%82%e4%bd%95%e6%b7%bb%e5%8a%a0fk%e5%a4%96","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/187462\/","title":{"rendered":"\u6578\u64da\u5eab\u65b0\u589eFK\u5916\u9375\u7684\u6b65\u9a5f\u8a73\u89e3 (\u6578\u64da\u5eab\u7684\u5982\u4f55\u6dfb\u52a0fk\u5916\u9375)"},"content":{"rendered":"<h1 id=\"%e6%95%b8%e6%93%9a%e5%ba%ab%e6%96%b0%e5%a2%9efk%e5%a4%96%e9%8d%b5%e7%9a%84%e6%ad%a5%e9%a9%9f%e8%a9%b3%e8%a7%a3-SmwyWcKgQU\">\u6578\u64da\u5eab\u65b0\u589eFK\u5916\u9375\u7684\u6b65\u9a5f\u8a73\u89e3<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u4e2d\uff0c\u5916\u9375\uff08Foreign Key\uff0c\u7c21\u7a31FK\uff09\u662f\u4e00\u500b\u91cd\u8981\u7684\u6982\u5ff5\u3002\u5b83\u7528\u65bc\u5efa\u7acb\u5169\u500b\u8868\u4e4b\u9593\u7684\u95dc\u806f\uff0c\u78ba\u4fdd\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u4e00\u81f4\u6027\u3002\u672c\u6587\u5c07\u8a73\u7d30\u4ecb\u7d39\u5982\u4f55\u5728\u6578\u64da\u5eab\u4e2d\u6dfb\u52a0\u5916\u9375\uff0c\u4e26\u63d0\u4f9b\u5177\u9ad4\u7684\u6b65\u9a5f\u548c\u793a\u4f8b\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e5%a4%96%e9%8d%b5%ef%bc%9f-SmwyWcKgQU\">\u4ec0\u9ebc\u662f\u5916\u9375\uff1f<\/h2>\n<p>\u5916\u9375\u662f\u4e00\u500b\u8868\u4e2d\u7684\u4e00\u500b\u6216\u591a\u500b\u5217\uff0c\u9019\u4e9b\u5217\u7684\u503c\u5fc5\u9808\u8207\u53e6\u4e00\u500b\u8868\u4e2d\u7684\u4e3b\u9375\uff08Primary Key\uff09\u6216\u552f\u4e00\u9375\uff08Unique Key\uff09\u76f8\u5339\u914d\u3002\u5916\u9375\u7684\u4e3b\u8981\u4f5c\u7528\u662f\u7dad\u8b77\u6578\u64da\u7684\u53c3\u7167\u5b8c\u6574\u6027\uff0c\u9632\u6b62\u51fa\u73fe\u5b64\u7acb\u7684\u6578\u64da\u3002<\/p>\n<h2 id=\"%e7%82%ba%e4%bb%80%e9%ba%bc%e9%9c%80%e8%a6%81%e5%a4%96%e9%8d%b5%ef%bc%9f-SmwyWcKgQU\">\u70ba\u4ec0\u9ebc\u9700\u8981\u5916\u9375\uff1f<\/h2>\n<ul>\n<li><strong>\u6578\u64da\u5b8c\u6574\u6027\uff1a<\/strong>\u5916\u9375\u53ef\u4ee5\u9632\u6b62\u63d2\u5165\u4e0d\u7b26\u5408\u908f\u8f2f\u7684\u6578\u64da\uff0c\u78ba\u4fdd\u6578\u64da\u4e4b\u9593\u7684\u95dc\u806f\u6027\u3002<\/li>\n<li><strong>\u6578\u64da\u4e00\u81f4\u6027\uff1a<\/strong>\u901a\u904e\u5916\u9375\uff0c\u7576\u4e3b\u8868\u4e2d\u7684\u6578\u64da\u88ab\u522a\u9664\u6216\u66f4\u65b0\u6642\uff0c\u76f8\u95dc\u7684\u5f9e\u8868\u6578\u64da\u4e5f\u53ef\u4ee5\u81ea\u52d5\u66f4\u65b0\u6216\u522a\u9664\u3002<\/li>\n<li><strong>\u67e5\u8a62\u6548\u7387\uff1a<\/strong>\u5916\u9375\u53ef\u4ee5\u5e6b\u52a9\u6578\u64da\u5eab\u512a\u5316\u67e5\u8a62\uff0c\u56e0\u70ba\u5b83\u5011\u63d0\u4f9b\u4e86\u8868\u4e4b\u9593\u7684\u95dc\u806f\u4fe1\u606f\u3002<\/li>\n<\/ul>\n<h2 id=\"%e6%b7%bb%e5%8a%a0%e5%a4%96%e9%8d%b5%e7%9a%84%e6%ad%a5%e9%a9%9f-SmwyWcKgQU\">\u6dfb\u52a0\u5916\u9375\u7684\u6b65\u9a5f<\/h2>\n<p>\u4ee5\u4e0b\u662f\u6dfb\u52a0\u5916\u9375\u7684\u5177\u9ad4\u6b65\u9a5f\uff0c\u9019\u88e1\u4ee5 MySQL \u6578\u64da\u5eab\u70ba\u4f8b\u9032\u884c\u8aaa\u660e\u3002<\/p>\n<h3 id=\"%e6%ad%a5%e9%a9%9f-1%ef%bc%9a%e5%89%b5%e5%bb%ba%e4%b8%bb%e8%a1%a8-SmwyWcKgQU\">\u6b65\u9a5f 1\uff1a\u5275\u5efa\u4e3b\u8868<\/h3>\n<p>\u9996\u5148\uff0c\u6211\u5011\u9700\u8981\u5275\u5efa\u4e00\u500b\u4e3b\u8868\uff0c\u9019\u500b\u8868\u5c07\u5305\u542b\u6211\u5011\u7684\u4e3b\u9375\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff0c\u5275\u5efa\u4e00\u500b\u540d\u70ba <code>users<\/code> \u7684\u8868\uff1a<\/p>\n<pre><code>CREATE TABLE users (\n    id INT AUTO_INCREMENT PRIMARY KEY,\n    username VARCHAR(50) NOT NULL\n);<\/code><\/pre>\n<h3 id=\"%e6%ad%a5%e9%a9%9f-2%ef%bc%9a%e5%89%b5%e5%bb%ba%e5%be%9e%e8%a1%a8-SmwyWcKgQU\">\u6b65\u9a5f 2\uff1a\u5275\u5efa\u5f9e\u8868<\/h3>\n<p>\u63a5\u4e0b\u4f86\uff0c\u6211\u5011\u9700\u8981\u5275\u5efa\u4e00\u500b\u5f9e\u8868\uff0c\u9019\u500b\u8868\u5c07\u5305\u542b\u5916\u9375\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff0c\u5275\u5efa\u4e00\u500b\u540d\u70ba <code>orders<\/code> \u7684\u8868\uff1a<\/p>\n<pre><code>CREATE TABLE orders (\n    order_id INT AUTO_INCREMENT PRIMARY KEY,\n    user_id INT,\n    order_date DATETIME,\n    FOREIGN KEY (user_id) REFERENCES users(id)\n);<\/code><\/pre>\n<h3 id=\"%e6%ad%a5%e9%a9%9f-3%ef%bc%9a%e6%b7%bb%e5%8a%a0%e5%a4%96%e9%8d%b5%e7%b4%84%e6%9d%9f-SmwyWcKgQU\">\u6b65\u9a5f 3\uff1a\u6dfb\u52a0\u5916\u9375\u7d04\u675f<\/h3>\n<p>\u5728\u5275\u5efa\u5f9e\u8868\u6642\uff0c\u6211\u5011\u53ef\u4ee5\u76f4\u63a5\u5728\u8868\u5b9a\u7fa9\u4e2d\u6dfb\u52a0\u5916\u9375\u7d04\u675f\uff0c\u5982\u4e0a\u9762\u7684\u793a\u4f8b\u6240\u793a\u3002\u5982\u679c\u9700\u8981\u5728\u5df2\u5b58\u5728\u7684\u8868\u4e2d\u6dfb\u52a0\u5916\u9375\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u8a9e\u53e5\uff1a<\/p>\n<pre><code>ALTER TABLE orders\nADD CONSTRAINT fk_user\nFOREIGN KEY (user_id) REFERENCES users(id);<\/code><\/pre>\n<h3 id=\"%e6%ad%a5%e9%a9%9f-4%ef%bc%9a%e6%aa%a2%e6%9f%a5%e5%a4%96%e9%8d%b5%e7%b4%84%e6%9d%9f-SmwyWcKgQU\">\u6b65\u9a5f 4\uff1a\u6aa2\u67e5\u5916\u9375\u7d04\u675f<\/h3>\n<p>\u6dfb\u52a0\u5916\u9375\u5f8c\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u8a9e\u53e5\u6aa2\u67e5\u5916\u9375\u7d04\u675f\u662f\u5426\u6210\u529f\u6dfb\u52a0\uff1a<\/p>\n<pre><code>SHOW CREATE TABLE orders;<\/code><\/pre>\n<p>\u9019\u5c07\u986f\u793a <code>orders<\/code> \u8868\u7684\u5275\u5efa\u8a9e\u53e5\uff0c\u5305\u62ec\u6240\u6709\u7684\u5916\u9375\u7d04\u675f\u3002<\/p>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-SmwyWcKgQU\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<ul>\n<li>\u78ba\u4fdd\u5916\u9375\u5217\u7684\u6578\u64da\u985e\u578b\u8207\u4e3b\u9375\u5217\u7684\u6578\u64da\u985e\u578b\u76f8\u540c\u3002<\/li>\n<li>\u5728\u6dfb\u52a0\u5916\u9375\u4e4b\u524d\uff0c\u78ba\u4fdd\u5f9e\u8868\u4e2d\u7684\u6578\u64da\u5df2\u7d93\u7b26\u5408\u5916\u9375\u7d04\u675f\u7684\u8981\u6c42\u3002<\/li>\n<li>\u5982\u679c\u9700\u8981\u522a\u9664\u5916\u9375\u7d04\u675f\uff0c\u53ef\u4ee5\u4f7f\u7528 <code>ALTER TABLE<\/code> \u8a9e\u53e5\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-SmwyWcKgQU\">\u7e3d\u7d50<\/h2>\n<p>\u5916\u9375\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u4e2d\u626e\u6f14\u8457\u81f3\u95dc\u91cd\u8981\u7684\u89d2\u8272\uff0c\u80fd\u5920\u6709\u6548\u5730\u7dad\u8b77\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u4e00\u81f4\u6027\u3002\u901a\u904e\u4e0a\u8ff0\u6b65\u9a5f\uff0c\u60a8\u53ef\u4ee5\u8f15\u9b06\u5730\u5728\u6578\u64da\u5eab\u4e2d\u6dfb\u52a0\u5916\u9375\uff0c\u5f9e\u800c\u5efa\u7acb\u8868\u4e4b\u9593\u7684\u95dc\u806f\u3002\u5982\u679c\u60a8\u9700\u8981\u66f4\u591a\u6709\u95dc <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u7684\u4fe1\u606f\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4ee5\u7372\u53d6\u66f4\u591a\u8cc7\u6e90\u548c\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u5728\u6578\u64da\u5eab\u4e2d\u65b0\u589eFK\u5916\u9375\u7684\u8a73\u7d30\u6b65\u9a5f\uff0c\u78ba\u4fdd\u6578\u64da\u5b8c\u6574\u6027\u8207\u95dc\u806f\u6027\uff0c\u63d0\u5347\u6578\u64da\u7ba1\u7406\u6548\u7387\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-187462","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/187462","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=187462"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/187462\/revisions"}],"predecessor-version":[{"id":187463,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/187462\/revisions\/187463"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=187462"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=187462"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=187462"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}