{"id":194543,"date":"2024-11-13T07:32:20","date_gmt":"2024-11-12T23:32:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/194543\/"},"modified":"2024-11-13T07:32:21","modified_gmt":"2024-11-12T23:32:21","slug":"%e7%94%a8mysql%e5%91%bd%e4%bb%a4%e5%b0%8d%e8%a1%a8%e5%92%8c%e7%9b%b8%e9%97%9c%e8%a1%a8%e7%b5%90%e6%a7%8b%e9%80%b2%e8%a1%8c%e4%bf%ae%e6%94%b9","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/194543\/","title":{"rendered":"\u7528MySQL\u547d\u4ee4\u5c0d\u8868\u548c\u76f8\u95dc\u8868\u7d50\u69cb\u9032\u884c\u4fee\u6539"},"content":{"rendered":"<h1 id=\"%e7%94%a8mysql%e5%91%bd%e4%bb%a4%e5%b0%8d%e8%a1%a8%e5%92%8c%e7%9b%b8%e9%97%9c%e8%a1%a8%e7%b5%90%e6%a7%8b%e9%80%b2%e8%a1%8c%e4%bf%ae%e6%94%b9-drNMhBzQID\">\u7528MySQL\u547d\u4ee4\u5c0d\u8868\u548c\u76f8\u95dc\u8868\u7d50\u69cb\u9032\u884c\u4fee\u6539<\/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\u7ba1\u7406\u7cfb\u7d71\u3002\u96a8\u8457\u696d\u52d9\u9700\u6c42\u7684\u8b8a\u5316\uff0c\u6578\u64da\u5eab\u7684\u7d50\u69cb\u4e5f\u9700\u8981\u9032\u884c\u76f8\u61c9\u7684\u8abf\u6574\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u4f7f\u7528MySQL\u547d\u4ee4\u5c0d\u8868\u53ca\u5176\u76f8\u95dc\u8868\u7d50\u69cb\u9032\u884c\u4fee\u6539\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u793a\u4f8b\u548c\u4ee3\u78bc\u7247\u6bb5\u3002<\/p>\n<h2 id=\"1-%e4%bf%ae%e6%94%b9%e8%a1%a8%e7%b5%90%e6%a7%8b%e7%9a%84%e5%9f%ba%e6%9c%ac%e5%91%bd%e4%bb%a4-drNMhBzQID\">1. \u4fee\u6539\u8868\u7d50\u69cb\u7684\u57fa\u672c\u547d\u4ee4<\/h2>\n<p>\u5728MySQL\u4e2d\uff0c\u4fee\u6539\u8868\u7d50\u69cb\u7684\u4e3b\u8981\u547d\u4ee4\u662fALTER TABLE\u3002\u9019\u500b\u547d\u4ee4\u53ef\u4ee5\u7528\u4f86\u6dfb\u52a0\u3001\u522a\u9664\u6216\u4fee\u6539\u8868\u4e2d\u7684\u5217\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u898b\u7684\u7528\u6cd5\uff1a<\/p>\n<h3 id=\"1-1-%e6%b7%bb%e5%8a%a0%e6%96%b0%e5%88%97-drNMhBzQID\">1.1 \u6dfb\u52a0\u65b0\u5217<\/h3>\n<p>\u8981\u5411\u8868\u4e2d\u6dfb\u52a0\u65b0\u5217\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d ADD \u5217\u540d \u6578\u64da\u985e\u578b;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70bausers\u7684\u8868\uff0c\u6211\u5011\u60f3\u8981\u6dfb\u52a0\u4e00\u500b\u540d\u70baage\u7684\u6574\u6578\u5217\uff1a<\/p>\n<pre><code>ALTER TABLE users ADD age INT;<\/code><\/pre>\n<h3 id=\"1-2-%e5%88%aa%e9%99%a4%e5%88%97-drNMhBzQID\">1.2 \u522a\u9664\u5217<\/h3>\n<p>\u5982\u679c\u9700\u8981\u522a\u9664\u67d0\u4e00\u5217\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d DROP COLUMN \u5217\u540d;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u522a\u9664users\u8868\u4e2d\u7684age\u5217\uff1a<\/p>\n<pre><code>ALTER TABLE users DROP COLUMN age;<\/code><\/pre>\n<h3 id=\"1-3-%e4%bf%ae%e6%94%b9%e5%88%97%e7%9a%84%e6%95%b8%e6%93%9a%e9%a1%9e%e5%9e%8b-drNMhBzQID\">1.3 \u4fee\u6539\u5217\u7684\u6578\u64da\u985e\u578b<\/h3>\n<p>\u8981\u4fee\u6539\u5217\u7684\u6578\u64da\u985e\u578b\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d MODIFY \u5217\u540d \u65b0\u6578\u64da\u985e\u578b;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c07users\u8868\u4e2d\u7684age\u5217\u4fee\u6539\u70baVARCHAR\u985e\u578b\uff1a<\/p>\n<pre><code>ALTER TABLE users MODIFY age VARCHAR(3);<\/code><\/pre>\n<h2 id=\"2-%e4%bf%ae%e6%94%b9%e4%b8%bb%e9%8d%b5%e5%92%8c%e7%b4%a2%e5%bc%95-drNMhBzQID\">2. \u4fee\u6539\u4e3b\u9375\u548c\u7d22\u5f15<\/h2>\n<p>\u5728\u6578\u64da\u5eab\u4e2d\uff0c\u4e3b\u9375\u548c\u7d22\u5f15\u5c0d\u65bc\u6578\u64da\u7684\u552f\u4e00\u6027\u548c\u67e5\u8a62\u6027\u80fd\u81f3\u95dc\u91cd\u8981\u3002\u4f7f\u7528ALTER TABLE\u547d\u4ee4\uff0c\u6211\u5011\u4e5f\u53ef\u4ee5\u4fee\u6539\u4e3b\u9375\u548c\u7d22\u5f15\u3002<\/p>\n<h3 id=\"2-1-%e6%b7%bb%e5%8a%a0%e4%b8%bb%e9%8d%b5-drNMhBzQID\">2.1 \u6dfb\u52a0\u4e3b\u9375<\/h3>\n<p>\u8981\u70ba\u8868\u6dfb\u52a0\u4e3b\u9375\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d ADD PRIMARY KEY (\u5217\u540d);<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u70bausers\u8868\u7684id\u5217\u6dfb\u52a0\u4e3b\u9375\uff1a<\/p>\n<pre><code>ALTER TABLE users ADD PRIMARY KEY (id);<\/code><\/pre>\n<h3 id=\"2-2-%e5%88%aa%e9%99%a4%e4%b8%bb%e9%8d%b5-drNMhBzQID\">2.2 \u522a\u9664\u4e3b\u9375<\/h3>\n<p>\u5982\u679c\u9700\u8981\u522a\u9664\u4e3b\u9375\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d DROP PRIMARY KEY;<\/code><\/pre>\n<h3 id=\"2-3-%e6%b7%bb%e5%8a%a0%e7%b4%a2%e5%bc%95-drNMhBzQID\">2.3 \u6dfb\u52a0\u7d22\u5f15<\/h3>\n<p>\u8981\u70ba\u8868\u6dfb\u52a0\u7d22\u5f15\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d ADD INDEX (\u5217\u540d);<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u70bausers\u8868\u7684email\u5217\u6dfb\u52a0\u7d22\u5f15\uff1a<\/p>\n<pre><code>ALTER TABLE users ADD INDEX (email);<\/code><\/pre>\n<h2 id=\"3-%e4%bf%ae%e6%94%b9%e5%a4%96%e9%8d%b5%e7%b4%84%e6%9d%9f-drNMhBzQID\">3. \u4fee\u6539\u5916\u9375\u7d04\u675f<\/h2>\n<p>\u5916\u9375\u7d04\u675f\u7528\u65bc\u7dad\u8b77\u8868\u4e4b\u9593\u7684\u53c3\u7167\u5b8c\u6574\u6027\u3002\u4f7f\u7528ALTER TABLE\u547d\u4ee4\uff0c\u6211\u5011\u53ef\u4ee5\u6dfb\u52a0\u6216\u522a\u9664\u5916\u9375\u7d04\u675f\u3002<\/p>\n<h3 id=\"3-1-%e6%b7%bb%e5%8a%a0%e5%a4%96%e9%8d%b5-drNMhBzQID\">3.1 \u6dfb\u52a0\u5916\u9375<\/h3>\n<p>\u8981\u70ba\u8868\u6dfb\u52a0\u5916\u9375\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d ADD CONSTRAINT \u5916\u9375\u540d FOREIGN KEY (\u5217\u540d) REFERENCES \u53c3\u8003\u8868(\u53c3\u8003\u5217);<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u70baorders\u8868\u7684user_id\u5217\u6dfb\u52a0\u5916\u9375\u7d04\u675f\uff0c\u53c3\u8003users\u8868\u7684id\u5217\uff1a<\/p>\n<pre><code>ALTER TABLE orders ADD CONSTRAINT fk_user FOREIGN KEY (user_id) REFERENCES users(id);<\/code><\/pre>\n<h3 id=\"3-2-%e5%88%aa%e9%99%a4%e5%a4%96%e9%8d%b5-drNMhBzQID\">3.2 \u522a\u9664\u5916\u9375<\/h3>\n<p>\u5982\u679c\u9700\u8981\u522a\u9664\u5916\u9375\u7d04\u675f\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>ALTER TABLE \u8868\u540d DROP FOREIGN KEY \u5916\u9375\u540d;<\/code><\/pre>\n<h2 id=\"4-%e5%b0%8f%e7%b5%90-drNMhBzQID\">4. \u5c0f\u7d50<\/h2>\n<p>\u901a\u904e\u4f7f\u7528MySQL\u7684ALTER TABLE\u547d\u4ee4\uff0c\u6211\u5011\u53ef\u4ee5\u9748\u6d3b\u5730\u5c0d\u8868\u53ca\u5176\u7d50\u69cb\u9032\u884c\u4fee\u6539\uff0c\u4ee5\u6eff\u8db3\u4e0d\u65b7\u8b8a\u5316\u7684\u696d\u52d9\u9700\u6c42\u3002\u7121\u8ad6\u662f\u6dfb\u52a0\u65b0\u5217\u3001\u4fee\u6539\u6578\u64da\u985e\u578b\uff0c\u9084\u662f\u7ba1\u7406\u4e3b\u9375\u548c\u5916\u9375\uff0c\u9019\u4e9b\u64cd\u4f5c\u90fd\u662f\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\u4e0d\u53ef\u6216\u7f3a\u7684\u4e00\u90e8\u5206\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u7a69\u5b9a\u4e14\u9ad8\u6548\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u670d\u52d9\uff0c\u9019\u5c07\u70ba\u60a8\u7684\u6578\u64da\u5eab\u63d0\u4f9b\u5f37\u5927\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u4f7f\u7528MySQL\u547d\u4ee4\u4fee\u6539\u8868\u53ca\u5176\u76f8\u95dc\u8868\u7d50\u69cb\uff0c\u63d0\u5347\u6578\u64da\u5eab\u7ba1\u7406\u6548\u7387\uff0c\u512a\u5316\u6578\u64da\u5b58\u5132\u548c\u67e5\u8a62\u6027\u80fd\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-194543","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/194543","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=194543"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/194543\/revisions"}],"predecessor-version":[{"id":194544,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/194543\/revisions\/194544"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=194543"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=194543"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=194543"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}