{"id":180870,"date":"2024-11-09T13:52:18","date_gmt":"2024-11-09T05:52:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/180870\/"},"modified":"2024-11-09T13:52:19","modified_gmt":"2024-11-09T05:52:19","slug":"%e6%b7%b1%e5%85%a5%e4%ba%86%e8%a7%a3%e5%8b%95%e7%b6%b2%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%97%e6%ae%b5%ef%bc%8c%e6%8e%8c%e6%8f%a1%e9%97%9c%e9%8d%b5%e6%93%8d%e4%bd%9c%e6%8a%80%e5%b7%a7-%e5%8b%95%e7%b6%b2","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/180870\/","title":{"rendered":"\u6df1\u5165\u4e86\u89e3\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\uff0c\u638c\u63e1\u95dc\u9375\u64cd\u4f5c\u6280\u5de7 (\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5)"},"content":{"rendered":"<h1 id=\"%e6%b7%b1%e5%85%a5%e4%ba%86%e8%a7%a3%e5%8b%95%e7%b6%b2%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%97%e6%ae%b5%ef%bc%8c%e6%8e%8c%e6%8f%a1%e9%97%9c%e9%8d%b5%e6%93%8d%e4%bd%9c%e6%8a%80%e5%b7%a7-cAGJbmPINl\">\u6df1\u5165\u4e86\u89e3\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\uff0c\u638c\u63e1\u95dc\u9375\u64cd\u4f5c\u6280\u5de7<\/h1>\n<p>\u5728\u7576\u4eca\u6578\u64da\u9a45\u52d5\u7684\u4e16\u754c\u4e2d\uff0c\u6578\u64da\u5eab\u7684\u7ba1\u7406\u548c\u64cd\u4f5c\u8b8a\u5f97\u8d8a\u4f86\u8d8a\u91cd\u8981\u3002\u52d5\u7db2\u6578\u64da\u5eab\u4f5c\u70ba\u4e00\u7a2e\u6d41\u884c\u7684\u6578\u64da\u5b58\u5132\u89e3\u6c7a\u65b9\u6848\uff0c\u5ee3\u6cdb\u61c9\u7528\u65bc\u5404\u7a2e\u7db2\u7ad9\u548c\u61c9\u7528\u7a0b\u5e8f\u4e2d\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\u7684\u7d50\u69cb\u53ca\u5176\u95dc\u9375\u64cd\u4f5c\u6280\u5de7\uff0c\u5e6b\u52a9\u8b80\u8005\u66f4\u597d\u5730\u7406\u89e3\u548c\u4f7f\u7528\u9019\u4e00\u5de5\u5177\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e5%8b%95%e7%b6%b2%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%97%e6%ae%b5%ef%bc%9f-cAGJbmPINl\">\u4ec0\u9ebc\u662f\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\uff1f<\/h2>\n<p>\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\u662f\u6578\u64da\u5eab\u4e2d\u7528\u4f86\u5b58\u5132\u7279\u5b9a\u985e\u578b\u6578\u64da\u7684\u57fa\u672c\u55ae\u4f4d\u3002\u6bcf\u500b\u5b57\u6bb5\u90fd\u6709\u5176\u7279\u5b9a\u7684\u6578\u64da\u985e\u578b\u548c\u5c6c\u6027\uff0c\u9019\u4e9b\u5c6c\u6027\u6c7a\u5b9a\u4e86\u5b57\u6bb5\u53ef\u4ee5\u5b58\u5132\u7684\u6578\u64da\u985e\u578b\u53ca\u5176\u884c\u70ba\u3002\u5e38\u898b\u7684\u6578\u64da\u985e\u578b\u5305\u62ec\u6574\u6578\u3001\u6d6e\u9ede\u6578\u3001\u5b57\u7b26\u4e32\u3001\u65e5\u671f\u7b49\u3002<\/p>\n<h3 id=\"%e5%ad%97%e6%ae%b5%e7%9a%84%e5%9f%ba%e6%9c%ac%e7%b5%90%e6%a7%8b-cAGJbmPINl\">\u5b57\u6bb5\u7684\u57fa\u672c\u7d50\u69cb<\/h3>\n<p>\u5728\u52d5\u7db2\u6578\u64da\u5eab\u4e2d\uff0c\u5b57\u6bb5\u901a\u5e38\u7531\u4ee5\u4e0b\u5e7e\u500b\u90e8\u5206\u7d44\u6210\uff1a<\/p>\n<ul>\n<li><strong>\u5b57\u6bb5\u540d\u7a31\uff1a<\/strong>\u7528\u65bc\u6a19\u8b58\u5b57\u6bb5\u7684\u540d\u7a31\uff0c\u61c9\u5177\u6709\u63cf\u8ff0\u6027\u3002<\/li>\n<li><strong>\u6578\u64da\u985e\u578b\uff1a<\/strong>\u5b9a\u7fa9\u5b57\u6bb5\u53ef\u4ee5\u5b58\u5132\u7684\u6578\u64da\u985e\u578b\uff0c\u4f8b\u5982 INT\u3001VARCHAR\u3001DATETIME \u7b49\u3002<\/li>\n<li><strong>\u7d04\u675f\u689d\u4ef6\uff1a<\/strong>\u7528\u65bc\u9650\u5236\u5b57\u6bb5\u7684\u6578\u64da\u8f38\u5165\uff0c\u4f8b\u5982 NOT NULL\u3001UNIQUE\u3001PRIMARY KEY \u7b49\u3002<\/li>\n<li><strong>\u9ed8\u8a8d\u503c\uff1a<\/strong>\u7576\u672a\u63d0\u4f9b\u6578\u64da\u6642\uff0c\u5b57\u6bb5\u7684\u9810\u8a2d\u503c\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%8b%95%e7%b6%b2%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%97%e6%ae%b5%e7%9a%84%e6%93%8d%e4%bd%9c%e6%8a%80%e5%b7%a7-cAGJbmPINl\">\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\u7684\u64cd\u4f5c\u6280\u5de7<\/h2>\n<p>\u638c\u63e1\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\u7684\u64cd\u4f5c\u6280\u5de7\u5c0d\u65bc\u6578\u64da\u7684\u6709\u6548\u7ba1\u7406\u81f3\u95dc\u91cd\u8981\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u95dc\u9375\u7684\u64cd\u4f5c\u6280\u5de7\uff1a<\/p>\n<h3 id=\"1-%e5%89%b5%e5%bb%ba%e5%ad%97%e6%ae%b5-cAGJbmPINl\">1. \u5275\u5efa\u5b57\u6bb5<\/h3>\n<p>\u5728\u5275\u5efa\u6578\u64da\u8868\u6642\uff0c\u53ef\u4ee5\u4f7f\u7528 SQL \u8a9e\u53e5\u4f86\u5b9a\u7fa9\u5b57\u6bb5\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>CREATE TABLE users (\n    id INT PRIMARY KEY AUTO_INCREMENT,\n    username VARCHAR(50) NOT NULL,\n    email VARCHAR(100) UNIQUE,\n    created_at DATETIME DEFAULT CURRENT_TIMESTAMP\n);<\/code><\/pre>\n<p>\u4e0a\u8ff0\u8a9e\u53e5\u5275\u5efa\u4e86\u4e00\u500b\u540d\u70ba <code>users<\/code> \u7684\u8868\uff0c\u4e26\u5b9a\u7fa9\u4e86\u56db\u500b\u5b57\u6bb5\u3002<\/p>\n<h3 id=\"2-%e4%bf%ae%e6%94%b9%e5%ad%97%e6%ae%b5-cAGJbmPINl\">2. \u4fee\u6539\u5b57\u6bb5<\/h3>\n<p>\u5982\u679c\u9700\u8981\u66f4\u6539\u5b57\u6bb5\u7684\u5c6c\u6027\uff0c\u53ef\u4ee5\u4f7f\u7528 <code>ALTER TABLE<\/code> \u8a9e\u53e5\u3002\u4f8b\u5982\uff0c\u5c07 <code>username<\/code> \u5b57\u6bb5\u7684\u9577\u5ea6\u5f9e 50 \u589e\u52a0\u5230 100\uff1a<\/p>\n<pre><code>ALTER TABLE users\nMODIFY username VARCHAR(100);<\/code><\/pre>\n<h3 id=\"3-%e5%88%aa%e9%99%a4%e5%ad%97%e6%ae%b5-cAGJbmPINl\">3. \u522a\u9664\u5b57\u6bb5<\/h3>\n<p>\u82e5\u8981\u522a\u9664\u4e0d\u518d\u9700\u8981\u7684\u5b57\u6bb5\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u53e5\uff1a<\/p>\n<pre><code>ALTER TABLE users\nDROP COLUMN email;<\/code><\/pre>\n<h3 id=\"4-%e6%9f%a5%e8%a9%a2%e5%ad%97%e6%ae%b5%e6%95%b8%e6%93%9a-cAGJbmPINl\">4. \u67e5\u8a62\u5b57\u6bb5\u6578\u64da<\/h3>\n<p>\u4f7f\u7528 <code>SELECT<\/code> \u8a9e\u53e5\u53ef\u4ee5\u67e5\u8a62\u7279\u5b9a\u5b57\u6bb5\u7684\u6578\u64da\u3002\u4f8b\u5982\uff0c\u67e5\u8a62\u6240\u6709\u7528\u6236\u7684 <code>username<\/code>\uff1a<\/p>\n<pre><code>SELECT username FROM users;<\/code><\/pre>\n<h2 id=\"%e6%9c%80%e4%bd%b3%e5%af%a6%e8%b8%90-cAGJbmPINl\">\u6700\u4f73\u5be6\u8e10<\/h2>\n<p>\u5728\u64cd\u4f5c\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\u6642\uff0c\u9075\u5faa\u4e00\u4e9b\u6700\u4f73\u5be6\u8e10\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u5eab\u7684\u6027\u80fd\u548c\u53ef\u7dad\u8b77\u6027\uff1a<\/p>\n<ul>\n<li>\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u985e\u578b\uff0c\u4ee5\u7bc0\u7701\u5b58\u5132\u7a7a\u9593\u3002<\/li>\n<li>\u70ba\u5e38\u7528\u7684\u67e5\u8a62\u5b57\u6bb5\u5efa\u7acb\u7d22\u5f15\uff0c\u4ee5\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\u3002<\/li>\n<li>\u5b9a\u671f\u5099\u4efd\u6578\u64da\uff0c\u4ee5\u9632\u6578\u64da\u4e1f\u5931\u3002<\/li>\n<li>\u4f7f\u7528\u4e8b\u52d9\u4f86\u78ba\u4fdd\u6578\u64da\u7684\u4e00\u81f4\u6027\u548c\u5b8c\u6574\u6027\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-cAGJbmPINl\">\u7e3d\u7d50<\/h2>\n<p>\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\u662f\u6578\u64da\u5eab\u8a2d\u8a08\u548c\u7ba1\u7406\u7684\u6838\u5fc3\u7d44\u6210\u90e8\u5206\u3002\u901a\u904e\u4e86\u89e3\u5b57\u6bb5\u7684\u7d50\u69cb\u53ca\u5176\u64cd\u4f5c\u6280\u5de7\uff0c\u60a8\u53ef\u4ee5\u66f4\u6709\u6548\u5730\u7ba1\u7406\u6578\u64da\uff0c\u63d0\u5347\u61c9\u7528\u7a0b\u5e8f\u7684\u6027\u80fd\u3002\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684\u6578\u64da\u5b58\u5132\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u4f86\u652f\u6301\u60a8\u7684\u52d5\u7db2\u6578\u64da\u5eab\u9700\u6c42\u3002\u7121\u8ad6\u662f\u5275\u5efa\u3001\u4fee\u6539\u9084\u662f\u67e5\u8a62\u5b57\u6bb5\uff0c\u638c\u63e1\u9019\u4e9b\u6280\u5de7\u5c07\u4f7f\u60a8\u5728\u6578\u64da\u7ba1\u7406\u4e0a\u6e38\u5203\u6709\u9918\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6df1\u5165\u4e86\u89e3\u52d5\u7db2\u6578\u64da\u5eab\u5b57\u6bb5\uff0c\u638c\u63e1\u95dc\u9375\u64cd\u4f5c\u6280\u5de7\uff0c\u63d0\u5347\u6578\u64da\u7ba1\u7406\u6548\u7387\uff0c\u52a9\u529b\u696d\u52d9\u6c7a\u7b56\u8207\u5206\u6790\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-180870","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/180870","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=180870"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/180870\/revisions"}],"predecessor-version":[{"id":180871,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/180870\/revisions\/180871"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=180870"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=180870"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=180870"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}