{"id":143901,"date":"2024-11-01T02:12:17","date_gmt":"2024-10-31T18:12:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/143901\/"},"modified":"2024-11-01T02:12:18","modified_gmt":"2024-10-31T18:12:18","slug":"sql-%e5%88%aa%e9%99%a4%e5%ad%97%e6%ae%b5%ef%bc%9a%e5%a6%82%e4%bd%95%e5%9c%a8%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8%e4%b8%ad%e5%88%aa%e9%99%a4%e6%9f%90%e5%80%8b%e5%ad%97%e6%ae%b5%ef%bc%9f-sql-%e5%88%aa","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/143901\/","title":{"rendered":"SQL \u522a\u9664\u5b57\u6bb5\uff1a\u5982\u4f55\u5728\u6578\u64da\u5eab\u8868\u4e2d\u522a\u9664\u67d0\u500b\u5b57\u6bb5\uff1f (sql \u522a\u9664\u5b57\u6bb5\u7684\u6578\u64da\u5eab\u8868)"},"content":{"rendered":"<h1 id=\"sql-%e5%88%aa%e9%99%a4%e5%ad%97%e6%ae%b5%ef%bc%9a%e5%a6%82%e4%bd%95%e5%9c%a8%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8%e4%b8%ad%e5%88%aa%e9%99%a4%e6%9f%90%e5%80%8b%e5%ad%97%e6%ae%b5%ef%bc%9f-pMMPzXwcTV\">SQL \u522a\u9664\u5b57\u6bb5\uff1a\u5982\u4f55\u5728\u6578\u64da\u5eab\u8868\u4e2d\u522a\u9664\u67d0\u500b\u5b57\u6bb5\uff1f<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u96a8\u8457\u696d\u52d9\u9700\u6c42\u7684\u8b8a\u5316\uff0c\u7d93\u5e38\u9700\u8981\u5c0d\u6578\u64da\u5eab\u8868\u9032\u884c\u8abf\u6574\uff0c\u5176\u4e2d\u4e00\u500b\u5e38\u898b\u7684\u64cd\u4f5c\u5c31\u662f\u522a\u9664\u5b57\u6bb5\u3002\u9019\u7bc7\u6587\u7ae0\u5c07\u6df1\u5165\u63a2\u8a0e\u5982\u4f55\u5728 SQL \u4e2d\u522a\u9664\u5b57\u6bb5\uff0c\u4e26\u63d0\u4f9b\u76f8\u95dc\u7684\u793a\u4f8b\u548c\u6ce8\u610f\u4e8b\u9805\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e5%ad%97%e6%ae%b5%ef%bc%9f-pMMPzXwcTV\">\u4ec0\u9ebc\u662f\u5b57\u6bb5\uff1f<\/h2>\n<p>\u5728\u6578\u64da\u5eab\u4e2d\uff0c\u5b57\u6bb5\u662f\u8868\u7684\u57fa\u672c\u7d44\u6210\u90e8\u5206\uff0c\u6bcf\u500b\u5b57\u6bb5\u4ee3\u8868\u4e00\u500b\u6578\u64da\u5c6c\u6027\u3002\u4f8b\u5982\uff0c\u5728\u4e00\u500b\u7528\u6236\u8868\u4e2d\uff0c\u53ef\u80fd\u6703\u6709\u7528\u6236\u540d\u3001\u96fb\u5b50\u90f5\u4ef6\u548c\u8a3b\u518a\u65e5\u671f\u7b49\u5b57\u6bb5\u3002\u6bcf\u500b\u5b57\u6bb5\u90fd\u6709\u5176\u6578\u64da\u985e\u578b\uff0c\u5982\u6574\u6578\u3001\u5b57\u7b26\u4e32\u6216\u65e5\u671f\u7b49\u3002<\/p>\n<h2 id=\"%e7%82%ba%e4%bb%80%e9%ba%bc%e9%9c%80%e8%a6%81%e5%88%aa%e9%99%a4%e5%ad%97%e6%ae%b5%ef%bc%9f-pMMPzXwcTV\">\u70ba\u4ec0\u9ebc\u9700\u8981\u522a\u9664\u5b57\u6bb5\uff1f<\/h2>\n<p>\u522a\u9664\u5b57\u6bb5\u7684\u539f\u56e0\u53ef\u80fd\u6709\u5f88\u591a\uff0c\u5305\u62ec\uff1a<\/p>\n<ul>\n<li>\u696d\u52d9\u9700\u6c42\u8b8a\u66f4\uff1a\u67d0\u4e9b\u5b57\u6bb5\u53ef\u80fd\u4e0d\u518d\u9700\u8981\uff0c\u6216\u8005\u5176\u6578\u64da\u4e0d\u518d\u76f8\u95dc\u3002<\/li>\n<li>\u6578\u64da\u5eab\u512a\u5316\uff1a\u522a\u9664\u4e0d\u5fc5\u8981\u7684\u5b57\u6bb5\u53ef\u4ee5\u6e1b\u5c11\u6578\u64da\u5eab\u7684\u5927\u5c0f\uff0c\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002<\/li>\n<li>\u6578\u64da\u4e00\u81f4\u6027\uff1a\u6709\u6642\u5019\uff0c\u67d0\u4e9b\u5b57\u6bb5\u7684\u6578\u64da\u53ef\u80fd\u6703\u5c0e\u81f4\u4e0d\u4e00\u81f4\u6216\u5197\u9918\uff0c\u522a\u9664\u5b83\u5011\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u7684\u6574\u9ad4\u8cea\u91cf\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%a6%82%e4%bd%95%e5%88%aa%e9%99%a4%e5%ad%97%e6%ae%b5%ef%bc%9f-pMMPzXwcTV\">\u5982\u4f55\u522a\u9664\u5b57\u6bb5\uff1f<\/h2>\n<p>\u5728 SQL \u4e2d\uff0c\u522a\u9664\u5b57\u6bb5\u7684\u64cd\u4f5c\u901a\u5e38\u4f7f\u7528 ALTER TABLE \u8a9e\u53e5\u3002\u4ee5\u4e0b\u662f\u57fa\u672c\u7684\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d DROP COLUMN \u5b57\u6bb5\u540d;<\/code><\/pre>\n<p>\u9019\u88e1\u7684\u201c\u8868\u540d\u201d\u662f\u4f60\u8981\u64cd\u4f5c\u7684\u8868\u7684\u540d\u7a31\uff0c\u800c\u201c\u5b57\u6bb5\u540d\u201d\u662f\u4f60\u60f3\u8981\u522a\u9664\u7684\u5b57\u6bb5\u7684\u540d\u7a31\u3002<\/p>\n<h3 id=\"%e7%a4%ba%e4%be%8b-pMMPzXwcTV\">\u793a\u4f8b<\/h3>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba <code>users<\/code> \u7684\u8868\uff0c\u7d50\u69cb\u5982\u4e0b\uff1a<\/p>\n<pre><code>CREATE TABLE users (\n    id INT PRIMARY KEY,\n    username VARCHAR(50),\n    email VARCHAR(100),\n    created_at DATETIME\n);<\/code><\/pre>\n<p>\u5982\u679c\u6211\u5011\u6c7a\u5b9a\u4e0d\u518d\u9700\u8981 <code>email<\/code> \u5b57\u6bb5\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u8a9e\u53e5\u4f86\u522a\u9664\u5b83\uff1a<\/p>\n<pre><code>ALTER TABLE users DROP COLUMN email;<\/code><\/pre>\n<p>\u57f7\u884c\u9019\u689d\u8a9e\u53e5\u5f8c\uff0c<code>users<\/code> \u8868\u5c07\u4e0d\u518d\u5305\u542b <code>email<\/code> \u5b57\u6bb5\u3002<\/p>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-pMMPzXwcTV\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u5728\u522a\u9664\u5b57\u6bb5\u4e4b\u524d\uff0c\u8acb\u8003\u616e\u4ee5\u4e0b\u5e7e\u9ede\uff1a<\/p>\n<ul>\n<li><strong>\u5099\u4efd\u6578\u64da\uff1a<\/strong>\u5728\u9032\u884c\u4efb\u4f55\u7d50\u69cb\u8b8a\u66f4\u4e4b\u524d\uff0c\u5efa\u8b70\u5099\u4efd\u6578\u64da\u5eab\uff0c\u4ee5\u9632\u6b62\u610f\u5916\u6578\u64da\u4e1f\u5931\u3002<\/li>\n<li><strong>\u6aa2\u67e5\u4f9d\u8cf4\u6027\uff1a<\/strong>\u78ba\u4fdd\u6c92\u6709\u5176\u4ed6\u8868\u6216\u61c9\u7528\u7a0b\u5e8f\u4f9d\u8cf4\u65bc\u4f60\u8981\u522a\u9664\u7684\u5b57\u6bb5\u3002<\/li>\n<li><strong>\u6e2c\u8a66\u74b0\u5883\uff1a<\/strong>\u5728\u751f\u7522\u74b0\u5883\u4e2d\u57f7\u884c\u4e4b\u524d\uff0c\u6700\u597d\u5728\u6e2c\u8a66\u74b0\u5883\u4e2d\u9a57\u8b49\u522a\u9664\u64cd\u4f5c\u7684\u5f71\u97ff\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-pMMPzXwcTV\">\u7d50\u8ad6<\/h2>\n<p>\u522a\u9664\u5b57\u6bb5\u662f\u4e00\u500b\u91cd\u8981\u7684\u6578\u64da\u5eab\u7ba1\u7406\u64cd\u4f5c\uff0c\u80fd\u5920\u5e6b\u52a9\u7dad\u6301\u6578\u64da\u7684\u6574\u6f54\u548c\u4e00\u81f4\u6027\u3002\u901a\u904e\u4f7f\u7528 <code>ALTER TABLE<\/code> \u8a9e\u53e5\uff0c\u60a8\u53ef\u4ee5\u8f15\u9b06\u5730\u5f9e\u6578\u64da\u5eab\u8868\u4e2d\u522a\u9664\u4e0d\u518d\u9700\u8981\u7684\u5b57\u6bb5\u3002\u5728\u9032\u884c\u6b64\u64cd\u4f5c\u6642\uff0c\u52d9\u5fc5\u8b39\u614e\uff0c\u4e26\u9075\u5faa\u6700\u4f73\u5be6\u8e10\uff0c\u4ee5\u78ba\u4fdd\u6578\u64da\u7684\u5b89\u5168\u548c\u5b8c\u6574\u6027\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK \u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u4e0d\u540c\u696d\u52d9\u9700\u6c42\u3002\u7121\u8ad6\u662f\u6578\u64da\u5eab\u7ba1\u7406\u9084\u662f\u5176\u4ed6\u61c9\u7528\uff0c\u9078\u64c7\u5408\u9069\u7684 <a href=\"https:\/\/server.hk\">\u4e91\u4f3a\u670d\u5668<\/a> \u5c07\u6709\u52a9\u65bc\u63d0\u5347\u60a8\u7684\u696d\u52d9\u6548\u7387\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u5728\u6578\u64da\u5eab\u8868\u4e2d\u4f7f\u7528 SQL \u522a\u9664\u5b57\u6bb5\uff0c\u7c21\u55ae\u6b65\u9a5f\u6559\u4f60\u6709\u6548\u7ba1\u7406\u6578\u64da\u7d50\u69cb\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-143901","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143901","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=143901"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143901\/revisions"}],"predecessor-version":[{"id":143902,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143901\/revisions\/143902"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=143901"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=143901"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=143901"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}