{"id":77150,"date":"2024-10-16T10:30:16","date_gmt":"2024-10-16T02:30:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/77150\/"},"modified":"2024-10-16T10:30:16","modified_gmt":"2024-10-16T02:30:16","slug":"mysql%e4%bf%ae%e6%94%b9%e8%a1%a8%e7%b5%90%e6%a7%8balter-%e5%af%a6%e6%93%8d","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/77150\/","title":{"rendered":"MySQL\u4fee\u6539\u8868\u7d50\u69cbalter \u5be6\u64cd"},"content":{"rendered":"<h1 id=\"mysql%e4%bf%ae%e6%94%b9%e8%a1%a8%e7%b5%90%e6%a7%8balter%e5%af%a6%e6%93%8d-gOLDaDWccz\">MySQL\u4fee\u6539\u8868\u7d50\u69cbALTER\u5be6\u64cd<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u95dc\u4fc2\u578b\u6578\u64da\u5eab\u7cfb\u7d71\u3002\u96a8\u8457\u696d\u52d9\u9700\u6c42\u7684\u8b8a\u5316\uff0c\u6578\u64da\u5eab\u7684\u7d50\u69cb\u4e5f\u9700\u8981\u9032\u884c\u8abf\u6574\u3002\u9019\u6642\uff0c<code>ALTER TABLE<\/code>\u8a9e\u53e5\u4fbf\u6210\u70ba\u4e86\u6211\u5011\u7684\u597d\u5e6b\u624b\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u5982\u4f55\u4f7f\u7528<code>ALTER TABLE<\/code>\u4f86\u4fee\u6539MySQL\u4e2d\u7684\u8868\u7d50\u69cb\uff0c\u4e26\u63d0\u4f9b\u5be6\u969b\u64cd\u4f5c\u7684\u793a\u4f8b\u3002<\/p>\n<h2 id=\"alter-table%e8%aa%9e%e6%b3%95%e6%a6%82%e8%bf%b0-gOLDaDWccz\">ALTER TABLE\u8a9e\u6cd5\u6982\u8ff0<\/h2>\n<p><code>ALTER TABLE<\/code>\u8a9e\u53e5\u7528\u65bc\u4fee\u6539\u5df2\u5b58\u5728\u7684\u8868\u7d50\u69cb\u3002\u5176\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>ALTER TABLE table_name\n    action;\n<\/code><\/pre>\n<p>\u5176\u4e2d\uff0c<code>table_name<\/code>\u662f\u8981\u4fee\u6539\u7684\u8868\u540d\uff0c<code>action<\/code>\u5247\u662f\u5177\u9ad4\u7684\u4fee\u6539\u64cd\u4f5c\uff0c\u5982\u6dfb\u52a0\u3001\u522a\u9664\u6216\u4fee\u6539\u5217\u7b49\u3002<\/p>\n<h2 id=\"%e5%b8%b8%e8%a6%8b%e7%9a%84alter-table%e6%93%8d%e4%bd%9c-gOLDaDWccz\">\u5e38\u898b\u7684ALTER TABLE\u64cd\u4f5c<\/h2>\n<h3 id=\"1-%e6%b7%bb%e5%8a%a0%e6%96%b0%e5%88%97-gOLDaDWccz\">1. \u6dfb\u52a0\u65b0\u5217<\/h3>\n<p>\u5982\u679c\u9700\u8981\u5728\u8868\u4e2d\u6dfb\u52a0\u65b0\u5217\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE table_name\n    ADD column_name column_type;\n<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba<code>employees<\/code>\u7684\u8868\uff0c\u73fe\u5728\u9700\u8981\u6dfb\u52a0\u4e00\u500b\u540d\u70ba<code>birthdate<\/code>\u7684\u65e5\u671f\u5217\uff1a<\/p>\n<pre><code>ALTER TABLE employees\n    ADD birthdate DATE;\n<\/code><\/pre>\n<h3 id=\"2-%e5%88%aa%e9%99%a4%e5%88%97-gOLDaDWccz\">2. \u522a\u9664\u5217<\/h3>\n<p>\u82e5\u8981\u522a\u9664\u8868\u4e2d\u7684\u67d0\u4e00\u5217\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE table_name\n    DROP COLUMN column_name;\n<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5f9e<code>employees<\/code>\u8868\u4e2d\u522a\u9664<code>birthdate<\/code>\u5217\uff1a<\/p>\n<pre><code>ALTER TABLE employees\n    DROP COLUMN birthdate;\n<\/code><\/pre>\n<h3 id=\"3-%e4%bf%ae%e6%94%b9%e5%88%97%e7%9a%84%e6%95%b8%e6%93%9a%e9%a1%9e%e5%9e%8b-gOLDaDWccz\">3. \u4fee\u6539\u5217\u7684\u6578\u64da\u985e\u578b<\/h3>\n<p>\u5982\u679c\u9700\u8981\u66f4\u6539\u67d0\u4e00\u5217\u7684\u6578\u64da\u985e\u578b\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE table_name\n    MODIFY COLUMN column_name new_column_type;\n<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c07<code>employees<\/code>\u8868\u4e2d\u7684<code>salary<\/code>\u5217\u7684\u6578\u64da\u985e\u578b\u5f9e<code>INT<\/code>\u6539\u70ba<code>DECIMAL(10,2)<\/code>\uff1a<\/p>\n<pre><code>ALTER TABLE employees\n    MODIFY COLUMN salary DECIMAL(10,2);\n<\/code><\/pre>\n<h3 id=\"4-%e9%87%8d%e5%91%bd%e5%90%8d%e5%88%97-gOLDaDWccz\">4. \u91cd\u547d\u540d\u5217<\/h3>\n<p>\u82e5\u8981\u91cd\u547d\u540d\u67d0\u4e00\u5217\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE table_name\n    CHANGE old_column_name new_column_name column_type;\n<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c07<code>employees<\/code>\u8868\u4e2d\u7684<code>salary<\/code>\u5217\u91cd\u547d\u540d\u70ba<code>monthly_salary<\/code>\uff1a<\/p>\n<pre><code>ALTER TABLE employees\n    CHANGE salary monthly_salary DECIMAL(10,2);\n<\/code><\/pre>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-gOLDaDWccz\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<ul>\n<li>\u5728\u9032\u884c\u7d50\u69cb\u4fee\u6539\u4e4b\u524d\uff0c\u5efa\u8b70\u5099\u4efd\u6578\u64da\uff0c\u4ee5\u9632\u6b62\u610f\u5916\u6578\u64da\u4e1f\u5931\u3002<\/li>\n<li>\u67d0\u4e9b\u64cd\u4f5c\u53ef\u80fd\u6703\u5f71\u97ff\u8868\u7684\u6027\u80fd\uff0c\u7279\u5225\u662f\u5728\u5927\u578b\u6578\u64da\u8868\u4e0a\u9032\u884c\u4fee\u6539\u6642\u3002<\/li>\n<li>\u5728\u4fee\u6539\u8868\u7d50\u69cb\u6642\uff0c\u8acb\u78ba\u4fdd\u6c92\u6709\u5176\u4ed6\u9032\u7a0b\u6b63\u5728\u4f7f\u7528\u8a72\u8868\uff0c\u4ee5\u907f\u514d\u9396\u5b9a\u554f\u984c\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-gOLDaDWccz\">\u7e3d\u7d50<\/h2>\n<p>\u4f7f\u7528<code>ALTER TABLE<\/code>\u8a9e\u53e5\u53ef\u4ee5\u9748\u6d3b\u5730\u4fee\u6539MySQL\u4e2d\u7684\u8868\u7d50\u69cb\uff0c\u6eff\u8db3\u4e0d\u65b7\u8b8a\u5316\u7684\u696d\u52d9\u9700\u6c42\u3002\u7121\u8ad6\u662f\u6dfb\u52a0\u65b0\u5217\u3001\u522a\u9664\u4e0d\u9700\u8981\u7684\u5217\uff0c\u9084\u662f\u4fee\u6539\u5217\u7684\u6578\u64da\u985e\u578b\uff0c\u9019\u4e9b\u64cd\u4f5c\u90fd\u80fd\u5920\u5e6b\u52a9\u6211\u5011\u66f4\u597d\u5730\u7ba1\u7406\u6578\u64da\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u7ba1\u7406\u7684\u4f01\u696d\u4f86\u8aaa\uff0c\u9078\u64c7\u5408\u9069\u7684<code><a href=\"https:\/\/server.hk\">VPS<\/a><\/code>\u6216<code><a href=\"https:\/\/server.hk\">\u9999\u6e2f\u4f3a\u670d\u5668<\/a><\/code>\u89e3\u6c7a\u65b9\u6848\u4e5f\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u5e0c\u671b\u672c\u6587\u80fd\u5920\u5e6b\u52a9\u60a8\u66f4\u597d\u5730\u7406\u89e3MySQL\u7684\u8868\u7d50\u69cb\u4fee\u6539\u64cd\u4f5c\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u4f7f\u7528MySQL\u7684ALTER\u8a9e\u53e5\u4fee\u6539\u8868\u7d50\u69cb\uff0c\u5be6\u64cd\u793a\u7bc4\u5305\u62ec\u6dfb\u52a0\u3001\u522a\u9664\u548c\u4fee\u6539\u6b04\u4f4d\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-77150","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/77150","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=77150"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/77150\/revisions"}],"predecessor-version":[{"id":77151,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/77150\/revisions\/77151"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=77150"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=77150"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=77150"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}