{"id":75132,"date":"2024-10-15T23:16:15","date_gmt":"2024-10-15T15:16:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/75132\/"},"modified":"2024-10-15T23:16:16","modified_gmt":"2024-10-15T15:16:16","slug":"mysql-%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%ef%bc%8c%e5%88%aa%e9%99%a4%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%e4%bf%9d%e7%95%99id%e6%9c%80%e5%b0%8f%e7%9a%84%e4%b8%80%e6%a2%9d%e4%bd%9c","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/75132\/","title":{"rendered":"MySQL \u67e5\u8a62\u91cd\u8907\u6578\u64da\uff0c\u522a\u9664\u91cd\u8907\u6578\u64da\u4fdd\u7559ID\u6700\u5c0f\u7684\u4e00\u689d\u4f5c\u70ba\u552f\u4e00\u6578\u64da"},"content":{"rendered":"<h1 id=\"mysql-%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%ef%bc%8c%e5%88%aa%e9%99%a4%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%e4%bf%9d%e7%95%99id%e6%9c%80%e5%b0%8f%e7%9a%84%e4%b8%80%e6%a2%9d%e4%bd%9c-CBxbzdJoID\">MySQL \u67e5\u8a62\u91cd\u8907\u6578\u64da\uff0c\u522a\u9664\u91cd\u8907\u6578\u64da\u4fdd\u7559ID\u6700\u5c0f\u7684\u4e00\u689d\u4f5c\u70ba\u552f\u4e00\u6578\u64da<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u91cd\u8907\u6578\u64da\u7684\u5b58\u5728\u53ef\u80fd\u6703\u5c0e\u81f4\u6578\u64da\u4e0d\u4e00\u81f4\u6027\uff0c\u5f71\u97ff\u67e5\u8a62\u7d50\u679c\u7684\u6e96\u78ba\u6027\u3002\u56e0\u6b64\uff0c\u5982\u4f55\u6709\u6548\u5730\u67e5\u8a62\u548c\u522a\u9664\u91cd\u8907\u6578\u64da\u6210\u70ba\u4e86\u6578\u64da\u5eab\u7ba1\u7406\u8005\u7684\u4e00\u9805\u91cd\u8981\u4efb\u52d9\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u5728 MySQL \u4e2d\u67e5\u8a62\u91cd\u8907\u6578\u64da\uff0c\u4e26\u522a\u9664\u91cd\u8907\u6578\u64da\uff0c\u540c\u6642\u4fdd\u7559 ID \u6700\u5c0f\u7684\u4e00\u689d\u4f5c\u70ba\u552f\u4e00\u6578\u64da\u3002<\/p>\n<h2 id=\"%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%e7%9a%84%e5%ae%9a%e7%be%a9-CBxbzdJoID\">\u91cd\u8907\u6578\u64da\u7684\u5b9a\u7fa9<\/h2>\n<p>\u91cd\u8907\u6578\u64da\u662f\u6307\u5728\u6578\u64da\u5eab\u4e2d\u5b58\u5728\u591a\u689d\u76f8\u540c\u6216\u76f8\u4f3c\u7684\u8a18\u9304\u3002\u9019\u4e9b\u8a18\u9304\u53ef\u80fd\u5728\u67d0\u4e9b\u5b57\u6bb5\u4e0a\u5b8c\u5168\u76f8\u540c\uff0c\u6216\u8005\u5728\u67d0\u4e9b\u5b57\u6bb5\u4e0a\u76f8\u4f3c\u3002\u91cd\u8907\u6578\u64da\u7684\u5b58\u5728\u6703\u5f71\u97ff\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u67e5\u8a62\u6548\u7387\uff0c\u56e0\u6b64\u9700\u8981\u5b9a\u671f\u9032\u884c\u6e05\u7406\u3002<\/p>\n<h2 id=\"%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a-CBxbzdJoID\">\u67e5\u8a62\u91cd\u8907\u6578\u64da<\/h2>\n<p>\u5728 MySQL \u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528 GROUP BY \u548c HAVING \u5b50\u53e5\u4f86\u67e5\u8a62\u91cd\u8907\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba <code>users<\/code> \u7684\u8868\uff0c\u8a72\u8868\u5305\u542b <code>id<\/code> \u548c <code>email<\/code> \u5b57\u6bb5\uff0c\u6211\u5011\u5e0c\u671b\u67e5\u8a62\u91cd\u8907\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\uff1a<\/p>\n<pre><code>SELECT email, COUNT(*) as count\nFROM users\nGROUP BY email\nHAVING count &gt; 1;<\/code><\/pre>\n<p>\u9019\u6bb5 SQL \u8a9e\u53e5\u5c07\u8fd4\u56de\u6240\u6709\u91cd\u8907\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u53ca\u5176\u51fa\u73fe\u7684\u6b21\u6578\u3002<\/p>\n<h2 id=\"%e5%88%aa%e9%99%a4%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a-CBxbzdJoID\">\u522a\u9664\u91cd\u8907\u6578\u64da<\/h2>\n<p>\u5728\u67e5\u8a62\u5230\u91cd\u8907\u6578\u64da\u5f8c\uff0c\u6211\u5011\u9700\u8981\u522a\u9664\u9019\u4e9b\u91cd\u8907\u7684\u8a18\u9304\uff0c\u53ea\u4fdd\u7559 ID \u6700\u5c0f\u7684\u4e00\u689d\u3002\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u8a9e\u53e5\u4f86\u5be6\u73fe\uff1a<\/p>\n<pre><code>DELETE u1\nFROM users u1\nINNER JOIN users u2 \nWHERE \n    u1.email = u2.email \n    AND u1.id &gt; u2.id;<\/code><\/pre>\n<p>\u9019\u6bb5 SQL \u8a9e\u53e5\u7684\u908f\u8f2f\u662f\uff1a\u901a\u904e\u81ea\u9023\u63a5 <code>users<\/code> \u8868\uff0c\u627e\u5230\u6240\u6709\u91cd\u8907\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\uff0c\u7136\u5f8c\u522a\u9664 ID \u5927\u65bc\u6700\u5c0f ID \u7684\u8a18\u9304\u3002\u9019\u6a23\u5c31\u80fd\u5920\u4fdd\u7559 ID \u6700\u5c0f\u7684\u4e00\u689d\u4f5c\u70ba\u552f\u4e00\u6578\u64da\u3002<\/p>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-CBxbzdJoID\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<ul>\n<li>\u5728\u57f7\u884c\u522a\u9664\u64cd\u4f5c\u4e4b\u524d\uff0c\u5efa\u8b70\u5148\u9032\u884c\u6578\u64da\u5099\u4efd\uff0c\u4ee5\u9632\u6b62\u610f\u5916\u522a\u9664\u91cd\u8981\u6578\u64da\u3002<\/li>\n<li>\u5728\u522a\u9664\u91cd\u8907\u6578\u64da\u5f8c\uff0c\u53ef\u4ee5\u8003\u616e\u5728\u76f8\u95dc\u5b57\u6bb5\u4e0a\u6dfb\u52a0\u552f\u4e00\u7d22\u5f15\uff0c\u4ee5\u9632\u6b62\u672a\u4f86\u518d\u6b21\u51fa\u73fe\u91cd\u8907\u6578\u64da\u3002<\/li>\n<li>\u5728\u9032\u884c\u5927\u898f\u6a21\u522a\u9664\u64cd\u4f5c\u6642\uff0c\u5efa\u8b70\u5206\u6279\u57f7\u884c\uff0c\u4ee5\u6e1b\u5c11\u5c0d\u6578\u64da\u5eab\u6027\u80fd\u7684\u5f71\u97ff\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-CBxbzdJoID\">\u7e3d\u7d50<\/h2>\n<p>\u5728 MySQL \u4e2d\u67e5\u8a62\u548c\u522a\u9664\u91cd\u8907\u6578\u64da\u662f\u4e00\u9805\u91cd\u8981\u7684\u6578\u64da\u7ba1\u7406\u4efb\u52d9\u3002\u901a\u904e\u4f7f\u7528 GROUP BY \u548c HAVING \u5b50\u53e5\uff0c\u6211\u5011\u53ef\u4ee5\u8f15\u9b06\u67e5\u8a62\u5230\u91cd\u8907\u7684\u8a18\u9304\uff0c\u4e26\u901a\u904e\u81ea\u9023\u63a5\u7684\u65b9\u5f0f\u522a\u9664\u591a\u9918\u7684\u6578\u64da\uff0c\u4fdd\u7559 ID \u6700\u5c0f\u7684\u4e00\u689d\u4f5c\u70ba\u552f\u4e00\u6578\u64da\u3002\u9019\u4e0d\u50c5\u80fd\u5920\u63d0\u9ad8\u6578\u64da\u7684\u5b8c\u6574\u6027\uff0c\u9084\u80fd\u63d0\u5347\u67e5\u8a62\u6548\u7387\u3002<\/p>\n<p>\u5982\u679c\u60a8\u9700\u8981\u66f4\u9ad8\u6548\u7684\u6578\u64da\u7ba1\u7406\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528\u6211\u5011\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2f VPS<\/a> \u670d\u52d9\uff0c\u63d0\u4f9b\u7a69\u5b9a\u7684\u6578\u64da\u5eab\u74b0\u5883\uff0c\u52a9\u60a8\u8f15\u9b06\u7ba1\u7406\u6578\u64da\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u5728MySQL\u4e2d\u67e5\u8a62\u548c\u522a\u9664\u91cd\u8907\u6578\u64da\uff0c\u4fdd\u7559ID\u6700\u5c0f\u7684\u4e00\u689d\u4f5c\u70ba\u552f\u4e00\u6578\u64da\uff0c\u78ba\u4fdd\u6578\u64da\u5eab\u7684\u6574\u6f54\u6027\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-75132","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75132","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=75132"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75132\/revisions"}],"predecessor-version":[{"id":75133,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75132\/revisions\/75133"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=75132"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=75132"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=75132"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}