{"id":200132,"date":"2025-05-06T12:04:52","date_gmt":"2025-05-06T04:04:52","guid":{"rendered":"https:\/\/server.hk\/cnblog\/200132\/"},"modified":"2025-05-06T12:04:52","modified_gmt":"2025-05-06T04:04:52","slug":"sql%e5%92%8c%e5%9f%ba%e6%9c%ac%e5%91%bd%e4%bb%a4%e7%ae%80%e4%bb%8b","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/200132\/","title":{"rendered":"SQL\u548c\u57fa\u672c\u547d\u4ee4\u7b80\u4ecb"},"content":{"rendered":"<p><b><\/b> <\/p>\n<h1>SQL\u548c\u57fa\u672c\u547d\u4ee4\u7b80\u4ecb<\/h1>\n<p>\u79ef\u7d2f\u77e5\u8bc6\uff0c\u80dc\u8fc7\u79ef\u84c4\u91d1\u94f6\uff01\u6bd5\u7adf\u5728\u6570\u636e\u5e93\u5f00\u53d1\u7684\u8fc7\u7a0b\u4e2d\uff0c\u4f1a\u9047\u5230\u5404\u79cd\u5404\u6837\u7684\u95ee\u9898\uff0c\u5f80\u5f80\u90fd\u662f\u4e00\u4e9b\u7ec6\u8282\u77e5\u8bc6\u70b9\u8fd8\u6ca1\u6709\u638c\u63e1\u597d\u800c\u5bfc\u81f4\u7684\uff0c\u56e0\u6b64\u57fa\u7840\u77e5\u8bc6\u70b9\u7684\u79ef\u7d2f\u662f\u5f88\u91cd\u8981\u7684\u3002\u4e0b\u9762\u672c\u6587\u300aSQL\u548c\u57fa\u672c\u547d\u4ee4\u7b80\u4ecb\u300b\uff0c\u5c31\u5e26\u5927\u5bb6\u8bb2\u89e3\u4e00\u4e0b\u77e5\u8bc6\u70b9\uff0c\u82e5\u662f\u4f60\u5bf9\u672c\u6587\u611f\u5174\u8da3\uff0c\u6216\u8005\u662f\u60f3\u641e\u61c2\u5176\u4e2d\u67d0\u4e2a\u77e5\u8bc6\u70b9\uff0c\u5c31\u8bf7\u4f60\u7ee7\u7eed\u5f80\u4e0b\u770b\u5427~<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.17golang.com\/uploads\/20240903\/172537023266d70f78908dd.jpg\" class=\"aligncenter\"><\/p>\n<h2> sql\u7b80\u4ecb <\/h2>\n<h2> \u4ec0\u4e48\u662f sql\uff1f <\/h2>\n<p>sql\uff08\u7ed3\u6784\u5316\u67e5\u8be2\u8bed\u8a00\uff09\u662f\u4e00\u79cd\u7528\u4e8e\u7ba1\u7406\u548c\u64cd\u4f5c\u5173\u7cfb\u6570\u636e\u5e93\u7684\u6807\u51c6\u7f16\u7a0b\u8bed\u8a00\u3002\u5b83\u5141\u8bb8\u7528\u6237\u521b\u5efa\u3001\u8bfb\u53d6\u3001\u66f4\u65b0\u548c\u5220\u9664\u6570\u636e\u5e93\u4e2d\u7684\u6570\u636e\u3002 sql \u63d0\u4f9b\u4e86\u4e00\u79cd\u4f7f\u7528\u7b80\u5355\u7684\u58f0\u660e\u6027\u8bed\u53e5\u4e0e\u6570\u636e\u5e93\u4ea4\u4e92\u7684\u65b9\u6cd5\u3002<\/p>\n<h2> \u4e3a\u4ec0\u4e48\u8981\u5b66\u4e60 sql\uff1f <\/h2>\n<p>\u5b66\u4e60 sql \u81f3\u5173\u91cd\u8981\uff0c\u539f\u56e0\u5982\u4e0b\uff1a<\/p>\n<ul>\n<li> <strong>\u6570\u636e\u7ba1\u7406<\/strong>\uff1asql\u662f\u7ba1\u7406\u548c\u67e5\u8be2\u5173\u7cfb\u6570\u636e\u5e93\u7684\u4e3b\u8981\u8bed\u8a00\uff0c\u5e7f\u6cdb\u5e94\u7528\u4e8e\u5404\u79cd\u5e94\u7528\u4e2d\u3002<\/li>\n<li> <strong>\u804c\u4e1a\u673a\u4f1a<\/strong>\uff1a\u719f\u7ec3\u638c\u63e1 sql \u5bf9\u4e8e\u8bb8\u591a it \u548c\u6570\u636e\u76f8\u5173\u89d2\u8272\u6765\u8bf4\u662f\u4e00\u9879\u5b9d\u8d35\u7684\u6280\u80fd\uff0c\u5305\u62ec\u6570\u636e\u5e93\u7ba1\u7406\u5458\u3001\u6570\u636e\u5206\u6790\u5e08\u548c\u8f6f\u4ef6\u5f00\u53d1\u4eba\u5458\u3002<\/li>\n<li> <strong>\u6570\u636e\u5206\u6790<\/strong>\uff1asql \u4f7f\u60a8\u80fd\u591f\u6267\u884c\u590d\u6742\u7684\u6570\u636e\u5206\u6790\u548c\u62a5\u544a\u4efb\u52a1\uff0c\u4ece\u800c\u66f4\u8f7b\u677e\u5730\u4ece\u5927\u578b\u6570\u636e\u96c6\u4e2d\u63d0\u53d6\u6709\u4ef7\u503c\u7684\u89c1\u89e3\u3002<\/li>\n<li> <strong>\u591a\u529f\u80fd\u6027<\/strong>\uff1asql \u7528\u4e8e\u8bb8\u591a\u6d41\u884c\u7684\u6570\u636e\u5e93\u7cfb\u7edf\uff0c\u4f8b\u5982 mysql\u3001postgresql \u548c microsoft sql server\uff0c\u4f7f\u5176\u6210\u4e3a\u8de8\u4e0d\u540c\u5e73\u53f0\u7684\u901a\u7528\u6280\u80fd\u3002<\/li>\n<\/ul>\n<h2> sql\u6570\u636e\u5e93\u548c\u8868\u64cd\u4f5c\u6307\u5357 <\/h2>\n<h2> \u6570\u636e\u5e93\u64cd\u4f5c <\/h2>\n<h3> \u521b\u5efa\u6570\u636e\u5e93 <\/h3>\n<pre>create database firstdb;\n<\/pre>\n<p>\u6ce8\u610f\uff1afirstdb \u662f\u6570\u636e\u5e93\u540d\u79f0\u3002<\/p>\n<h3> \u4f7f\u7528\u6570\u636e\u5e93 <\/h3>\n<pre>use firstdb;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u5c06\u9009\u62e9\u8981\u4f7f\u7528\u7684\u6570\u636e\u5e93\u3002<\/p>\n<h3> \u5220\u9664\u6570\u636e\u5e93 <\/h3>\n<pre>drop database firstdb;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u5c06\u6c38\u4e45\u5220\u9664\u6570\u636e\u5e93\u53ca\u5176\u6240\u6709\u5185\u5bb9\u3002<\/p>\n<h3> \u66f4\u6539\u6570\u636e\u5e93\uff08\u8bbe\u7f6e\u4e3a\u53ea\u8bfb\uff09 <\/h3>\n<pre>alter database firstdb read only = 1;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u4f1a\u4f7f\u6570\u636e\u5e93\u53ea\u8bfb\uff0c\u9632\u6b62\u4efb\u4f55\u4fee\u6539\u3002<\/p>\n<h2> \u8868\u64cd\u4f5c <\/h2>\n<h3> \u521b\u5efa\u8868 <\/h3>\n<pre>create table student (\n    student_id int,\n    first_name varchar(30),\n    last_name varchar(50),\n    student_address varchar(50),\n    hourly_pay decimal(5,2),\n    student_date date\n);\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u5c06\u521b\u5efa\u4e00\u4e2a\u540d\u4e3a\u201cstudent\u201d\u7684\u8868\uff0c\u5176\u4e2d\u5305\u542b\u6307\u5b9a\u7684\u5217\u548c\u6570\u636e\u7c7b\u578b\u3002<\/p>\n<h3> \u4ece\u8868\u4e2d\u9009\u62e9\u6240\u6709\u6570\u636e <\/h3>\n<pre>select * from student;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u5c06\u4ece\u201c\u5b66\u751f\u201d\u8868\u4e2d\u68c0\u7d22\u6240\u6709\u884c\u548c\u5217\u3002<\/p>\n<h3> \u91cd\u547d\u540d\u8868 <\/h3>\n<pre>rename table student to students;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u4f1a\u5c06\u8868\u540d\u79f0\u4ece\u201cstudent\u201d\u66f4\u6539\u4e3a\u201cstudents\u201d\u3002<\/p>\n<h2> \u6539\u53d8\u8868\u7ed3\u6784 <\/h2>\n<h3> \u6dfb\u52a0\u65b0\u5217 <\/h3>\n<pre>alter table students\nadd phone_number varchar(15);\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u4f1a\u5728\u201c\u5b66\u751f\u201d\u8868\u4e2d\u6dfb\u52a0\u4e00\u4e2a\u65b0\u5217\u201cphone_number\u201d\u3002<\/p>\n<h3> \u91cd\u547d\u540d\u5217 <\/h3>\n<pre>alter table students\nchange phone_number email varchar(100);\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u4f1a\u5c06\u5217\u540d\u79f0\u4ece\u201cphone_number\u201d\u66f4\u6539\u4e3a\u201cemail\u201d\u5e76\u4fee\u6539\u5176\u6570\u636e\u7c7b\u578b\u3002<\/p>\n<h3> \u4fee\u6539\u5217\u7684\u6570\u636e\u7c7b\u578b <\/h3>\n<pre>alter table students \nmodify column email varchar(100);\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u4f1a\u5c06\u201c\u7535\u5b50\u90ae\u4ef6\u201d\u5217\u7684\u6570\u636e\u7c7b\u578b\u66f4\u6539\u4e3a varchar(100)\u3002<\/p>\n<h3> \u66f4\u6539\u5217\u7684\u4f4d\u7f6e <\/h3>\n<pre>alter table students\nmodify email varchar(100) after last_name;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u4f1a\u5c06\u201c\u7535\u5b50\u90ae\u4ef6\u201d\u5217\u79fb\u52a8\u5230\u201c\u59d3\u6c0f\u201d\u5217\u4e4b\u540e\u3002<\/p>\n<pre>alter table students\nmodify email varchar(100) first;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u4f1a\u5c06\u201c\u7535\u5b50\u90ae\u4ef6\u201d\u5217\u79fb\u52a8\u5230\u8868\u4e2d\u7684\u7b2c\u4e00\u5217\u3002<\/p>\n<h3> \u5220\u9664\u4e00\u5217 <\/h3>\n<pre>alter table students\ndrop column email;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u5c06\u4ece\u8868\u4e2d\u6c38\u4e45\u5220\u9664\u201c\u7535\u5b50\u90ae\u4ef6\u201d\u5217\u3002<\/p>\n<h3> \u7ec4\u5408\u591a\u4e2a\u64cd\u4f5c <\/h3>\n<pre>ALTER TABLE students\nMODIFY email VARCHAR(100) AFTER last_name;\nSELECT * FROM students;\n<\/pre>\n<p>\u6ce8\u610f\uff1a\u8fd9\u4f1a\u66f4\u6539\u5217\u4f4d\u7f6e\uff0c\u7136\u540e\u5728\u4e00\u6b21\u64cd\u4f5c\u4e2d\u663e\u793a\u65b0\u7684\u8868\u7ed3\u6784\u3002<\/p>\n<p>\u4eca\u5929\u5173\u4e8e\u300aSQL\u548c\u57fa\u672c\u547d\u4ee4\u7b80\u4ecb\u300b\u7684\u5185\u5bb9\u4ecb\u7ecd\u5c31\u5230\u6b64\u7ed3\u675f\uff0c\u5982\u679c\u6709\u4ec0\u4e48\u7591\u95ee\u6216\u8005\u5efa\u8bae\uff0c\u53ef\u4ee5\u5728\u4e3b\u673a\u5b9d\u8d1d\u516c\u4f17\u53f7\u4e0b\u591a\u591a\u56de\u590d\u4ea4\u6d41\uff1b\u6587\u4e2d\u82e5\u6709\u4e0d\u6b63\u4e4b\u5904\uff0c\u4e5f\u5e0c\u671b\u56de\u590d\u7559\u8a00\u4ee5\u544a\u77e5\uff01<\/p>\n<p> \u7248\u672c\u58f0\u660e \u672c\u6587\u8f6c\u8f7d\u4e8e\uff1adev.to \u5982\u6709\u4fb5\u72af\uff0c\u8bf7\u8054\u7cfb \u5220\u9664 <\/p>\n<dl>\n<dt>\n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"<p>SQL\u548c\u57fa\u672c\u547d\u4ee4\u7b80\u4ecb \u79ef\u7d2f\u77e5\u8bc6\uff0c&#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-200132","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200132","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"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=200132"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200132\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=200132"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=200132"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=200132"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}