{"id":186928,"date":"2024-11-11T10:00:27","date_gmt":"2024-11-11T02:00:27","guid":{"rendered":"https:\/\/server.hk\/cnblog\/186928\/"},"modified":"2024-11-11T10:00:28","modified_gmt":"2024-11-11T02:00:28","slug":"%e6%95%b8%e6%93%9a%e5%ba%ab%e9%bb%98%e8%aa%8d%e5%80%bc%e7%9a%84%e5%90%ab%e7%be%a9%e5%8f%8a%e8%a8%ad%e7%bd%ae%e6%96%b9%e6%b3%95-%e6%95%b8%e6%93%9a%e5%ba%ab%e7%9a%84%e9%bb%98%e8%aa%8d%e5%80%bc%e6%98%af","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/186928\/","title":{"rendered":"\u6578\u64da\u5eab\u9ed8\u8a8d\u503c\u7684\u542b\u7fa9\u53ca\u8a2d\u7f6e\u65b9\u6cd5 (\u6578\u64da\u5eab\u7684\u9ed8\u8a8d\u503c\u662f\u4ec0\u9ebc)"},"content":{"rendered":"<h1 id=\"%e6%95%b8%e6%93%9a%e5%ba%ab%e9%bb%98%e8%aa%8d%e5%80%bc%e7%9a%84%e5%90%ab%e7%be%a9%e5%8f%8a%e8%a8%ad%e7%bd%ae%e6%96%b9%e6%b3%95-vgxcKMNcSV\">\u6578\u64da\u5eab\u9ed8\u8a8d\u503c\u7684\u542b\u7fa9\u53ca\u8a2d\u7f6e\u65b9\u6cd5<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u4e2d\uff0c\u9ed8\u8a8d\u503c\u662f\u4e00\u500b\u91cd\u8981\u7684\u6982\u5ff5\u3002\u5b83\u6307\u7684\u662f\u5728\u63d2\u5165\u65b0\u8a18\u9304\u6642\uff0c\u5982\u679c\u67d0\u500b\u5b57\u6bb5\u6c92\u6709\u88ab\u660e\u78ba\u6307\u5b9a\u503c\uff0c\u5247\u81ea\u52d5\u4f7f\u7528\u7684\u503c\u3002\u9019\u6a23\u7684\u8a2d\u7f6e\u4e0d\u50c5\u80fd\u63d0\u9ad8\u6578\u64da\u7684\u5b8c\u6574\u6027\uff0c\u9084\u80fd\u7c21\u5316\u6578\u64da\u7684\u7ba1\u7406\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u6578\u64da\u5eab\u9ed8\u8a8d\u503c\u7684\u542b\u7fa9\u53ca\u5176\u8a2d\u7f6e\u65b9\u6cd5\u3002<\/p>\n<h2 id=\"%e9%bb%98%e8%aa%8d%e5%80%bc%e7%9a%84%e6%84%8f%e7%be%a9-vgxcKMNcSV\">\u9ed8\u8a8d\u503c\u7684\u610f\u7fa9<\/h2>\n<p>\u9ed8\u8a8d\u503c\u7684\u4e3b\u8981\u76ee\u7684\u662f\u70ba\u4e86\u78ba\u4fdd\u6578\u64da\u7684\u4e00\u81f4\u6027\u548c\u5b8c\u6574\u6027\u3002\u7576\u7528\u6236\u5728\u63d2\u5165\u6578\u64da\u6642\uff0c\u53ef\u80fd\u6703\u5fd8\u8a18\u586b\u5beb\u67d0\u4e9b\u5b57\u6bb5\uff0c\u9019\u6642\u5019\u9ed8\u8a8d\u503c\u5c31\u80fd\u81ea\u52d5\u586b\u5145\u9019\u4e9b\u5b57\u6bb5\uff0c\u907f\u514d\u51fa\u73fe\u7a7a\u503c\u6216\u4e0d\u4e00\u81f4\u7684\u6578\u64da\u3002\u4f8b\u5982\uff0c\u5728\u4e00\u500b\u7528\u6236\u8cc7\u6599\u8868\u4e2d\uff0c\u5982\u679c\u7528\u6236\u7684\u5e74\u9f61\u5b57\u6bb5\u6c92\u6709\u88ab\u586b\u5beb\uff0c\u53ef\u4ee5\u8a2d\u7f6e\u9ed8\u8a8d\u503c\u70ba0\u6216NULL\uff0c\u9019\u6a23\u53ef\u4ee5\u907f\u514d\u6578\u64da\u5eab\u4e2d\u51fa\u73fe\u4e0d\u5b8c\u6574\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e8%a8%ad%e7%bd%ae%e9%bb%98%e8%aa%8d%e5%80%bc%e7%9a%84%e6%96%b9%e6%b3%95-vgxcKMNcSV\">\u8a2d\u7f6e\u9ed8\u8a8d\u503c\u7684\u65b9\u6cd5<\/h2>\n<p>\u8a2d\u7f6e\u9ed8\u8a8d\u503c\u7684\u65b9\u6cd5\u56e0\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\uff08DBMS\uff09\u800c\u7570\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u898b\u7684\u6578\u64da\u5eab\u7cfb\u7d71\u4e2d\u8a2d\u7f6e\u9ed8\u8a8d\u503c\u7684\u793a\u4f8b\uff1a<\/p>\n<h3 id=\"1-mysql-vgxcKMNcSV\">1. MySQL<\/h3>\n<p>\u5728MySQL\u4e2d\uff0c\u53ef\u4ee5\u5728\u5275\u5efa\u8868\u6642\u4f7f\u7528DEFAULT\u95dc\u9375\u5b57\u4f86\u8a2d\u7f6e\u9ed8\u8a8d\u503c\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>CREATE TABLE users (\n    id INT AUTO_INCREMENT PRIMARY KEY,\n    username VARCHAR(50) NOT NULL,\n    age INT DEFAULT 0\n);<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u7576\u63d2\u5165\u4e00\u500b\u65b0\u7528\u6236\u6642\uff0c\u5982\u679c\u6c92\u6709\u63d0\u4f9b\u5e74\u9f61\uff0c\u5247\u9ed8\u8a8d\u503c\u5c07\u8a2d\u7f6e\u70ba0\u3002<\/p>\n<h3 id=\"2-postgresql-vgxcKMNcSV\">2. PostgreSQL<\/h3>\n<p>PostgreSQL\u7684\u8a2d\u7f6e\u65b9\u6cd5\u8207MySQL\u985e\u4f3c\uff0c\u540c\u6a23\u4f7f\u7528DEFAULT\u95dc\u9375\u5b57\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>CREATE TABLE employees (\n    id SERIAL PRIMARY KEY,\n    name VARCHAR(100) NOT NULL,\n    department VARCHAR(50) DEFAULT 'General'\n);<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0c\u5982\u679c\u6c92\u6709\u6307\u5b9a\u90e8\u9580\uff0c\u5247\u9ed8\u8a8d\u90e8\u9580\u5c07\u8a2d\u7f6e\u70ba&#8217;General&#8217;\u3002<\/p>\n<h3 id=\"3-sql-server-vgxcKMNcSV\">3. SQL Server<\/h3>\n<p>\u5728SQL Server\u4e2d\uff0c\u8a2d\u7f6e\u9ed8\u8a8d\u503c\u7684\u8a9e\u6cd5\u4e5f\u76f8\u4f3c\uff0c\u53ef\u4ee5\u5728\u5275\u5efa\u8868\u6642\u4f7f\u7528DEFAULT\u7d04\u675f\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>CREATE TABLE products (\n    product_id INT PRIMARY KEY,\n    product_name NVARCHAR(100) NOT NULL,\n    price DECIMAL(10, 2) DEFAULT 0.00\n);<\/code><\/pre>\n<p>\u9019\u6a23\uff0c\u5982\u679c\u5728\u63d2\u5165\u7522\u54c1\u6642\u672a\u63d0\u4f9b\u50f9\u683c\uff0c\u5247\u9ed8\u8a8d\u50f9\u683c\u5c07\u70ba0.00\u3002<\/p>\n<h2 id=\"%e4%bf%ae%e6%94%b9%e9%bb%98%e8%aa%8d%e5%80%bc-vgxcKMNcSV\">\u4fee\u6539\u9ed8\u8a8d\u503c<\/h2>\n<p>\u5982\u679c\u9700\u8981\u4fee\u6539\u5df2\u5b58\u5728\u5b57\u6bb5\u7684\u9ed8\u8a8d\u503c\uff0c\u53ef\u4ee5\u4f7f\u7528ALTER TABLE\u8a9e\u53e5\u3002\u4ee5\u4e0b\u662fMySQL\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>ALTER TABLE users\nMODIFY age INT DEFAULT 18;<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u7528\u6236\u8868\u4e2d\u7684\u5e74\u9f61\u5b57\u6bb5\u7684\u9ed8\u8a8d\u503c\u4fee\u6539\u70ba18\u3002<\/p>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-vgxcKMNcSV\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<ul>\n<li>\u8a2d\u7f6e\u9ed8\u8a8d\u503c\u6642\uff0c\u61c9\u8003\u616e\u696d\u52d9\u908f\u8f2f\uff0c\u9078\u64c7\u5408\u9069\u7684\u9ed8\u8a8d\u503c\u4ee5\u907f\u514d\u6578\u64da\u932f\u8aa4\u3002<\/li>\n<li>\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u4f7f\u7528NULL\u4f5c\u70ba\u9ed8\u8a8d\u503c\u53ef\u80fd\u66f4\u5408\u9069\uff0c\u7279\u5225\u662f\u7576\u8a72\u5b57\u6bb5\u662f\u53ef\u9078\u7684\u6642\u5019\u3002<\/li>\n<li>\u5728\u8a2d\u8a08\u6578\u64da\u5eab\u6642\uff0c\u61c9\u8a72\u4ed4\u7d30\u8003\u616e\u6bcf\u500b\u5b57\u6bb5\u7684\u9ed8\u8a8d\u503c\uff0c\u4ee5\u78ba\u4fdd\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u4e00\u81f4\u6027\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-vgxcKMNcSV\">\u7e3d\u7d50<\/h2>\n<p>\u6578\u64da\u5eab\u7684\u9ed8\u8a8d\u503c\u662f\u4e00\u500b\u95dc\u9375\u7684\u8a2d\u8a08\u5143\u7d20\uff0c\u80fd\u5920\u5e6b\u52a9\u958b\u767c\u8005\u7dad\u8b77\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u4e00\u81f4\u6027\u3002\u901a\u904e\u5408\u7406\u8a2d\u7f6e\u9ed8\u8a8d\u503c\uff0c\u53ef\u4ee5\u7c21\u5316\u6578\u64da\u63d2\u5165\u904e\u7a0b\uff0c\u6e1b\u5c11\u932f\u8aa4\u767c\u751f\u7684\u6a5f\u6703\u3002\u7121\u8ad6\u662f\u4f7f\u7528MySQL\u3001PostgreSQL\u9084\u662fSQL Server\uff0c\u8a2d\u7f6e\u9ed8\u8a8d\u503c\u7684\u65b9\u6cd5\u90fd\u76f8\u5c0d\u7c21\u55ae\uff0c\u958b\u767c\u8005\u61c9\u6839\u64da\u5177\u9ad4\u9700\u6c42\u9078\u64c7\u5408\u9069\u7684\u9ed8\u8a8d\u503c\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK \u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u4e0d\u540c\u7528\u6236\u7684\u9700\u6c42\u3002\u7121\u8ad6\u662f <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u9084\u662f\u5176\u4ed6\u670d\u52d9\uff0c\u6211\u5011\u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u53ef\u9760\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u6578\u64da\u5eab\u9ed8\u8a8d\u503c\u7684\u542b\u7fa9\u53ca\u5176\u8a2d\u7f6e\u65b9\u6cd5\uff0c\u5e6b\u52a9\u60a8\u512a\u5316\u6578\u64da\u7ba1\u7406\u548c\u63d0\u9ad8\u6578\u64da\u4e00\u81f4\u6027\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-186928","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186928","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=186928"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186928\/revisions"}],"predecessor-version":[{"id":186929,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186928\/revisions\/186929"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=186928"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=186928"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=186928"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}