{"id":75828,"date":"2024-10-16T01:34:16","date_gmt":"2024-10-15T17:34:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/75828\/"},"modified":"2024-10-16T01:34:16","modified_gmt":"2024-10-15T17:34:16","slug":"mysql-%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e5%87%ba%e7%8f%be%e6%ac%a1%e6%95%b8%e6%9c%80%e5%a4%9a%e7%9a%84%e8%a8%98%e9%8c%84","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/75828\/","title":{"rendered":"MySQL \u67e5\u8a62\u91cd\u8907\u51fa\u73fe\u6b21\u6578\u6700\u591a\u7684\u8a18\u9304"},"content":{"rendered":"<h1 id=\"mysql-%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e5%87%ba%e7%8f%be%e6%ac%a1%e6%95%b8%e6%9c%80%e5%a4%9a%e7%9a%84%e8%a8%98%e9%8c%84-rKmgZlmJIM\">MySQL \u67e5\u8a62\u91cd\u8907\u51fa\u73fe\u6b21\u6578\u6700\u591a\u7684\u8a18\u9304<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0cMySQL \u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u95dc\u806f\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u3002\u7576\u6211\u5011\u9700\u8981\u5206\u6790\u6578\u64da\u6642\uff0c\u67e5\u8a62\u91cd\u8907\u51fa\u73fe\u6b21\u6578\u6700\u591a\u7684\u8a18\u9304\u662f\u4e00\u500b\u5e38\u898b\u7684\u9700\u6c42\u3002\u9019\u7bc7\u6587\u7ae0\u5c07\u4ecb\u7d39\u5982\u4f55\u4f7f\u7528 MySQL \u67e5\u8a62\u4f86\u627e\u51fa\u91cd\u8907\u51fa\u73fe\u7684\u8a18\u9304\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u7bc4\u4f8b\u548c\u4ee3\u78bc\u3002<\/p>\n<h2 id=\"%e7%82%ba%e4%bb%80%e9%ba%bc%e9%9c%80%e8%a6%81%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84-rKmgZlmJIM\">\u70ba\u4ec0\u9ebc\u9700\u8981\u67e5\u8a62\u91cd\u8907\u8a18\u9304<\/h2>\n<p>\u5728\u6578\u64da\u5206\u6790\u4e2d\uff0c\u91cd\u8907\u8a18\u9304\u53ef\u80fd\u6703\u5f71\u97ff\u6578\u64da\u7684\u6e96\u78ba\u6027\u548c\u5b8c\u6574\u6027\u3002\u901a\u904e\u8b58\u5225\u548c\u8655\u7406\u9019\u4e9b\u91cd\u8907\u8a18\u9304\uff0c\u4f01\u696d\u53ef\u4ee5\u66f4\u597d\u5730\u7406\u89e3\u5176\u6578\u64da\uff0c\u4e26\u505a\u51fa\u66f4\u660e\u667a\u7684\u6c7a\u7b56\u3002\u4f8b\u5982\uff0c\u5728\u5ba2\u6236\u6578\u64da\u4e2d\uff0c\u91cd\u8907\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u53ef\u80fd\u6703\u5c0e\u81f4\u91cd\u8907\u7684\u884c\u92b7\u6d3b\u52d5\uff0c\u5f9e\u800c\u6d6a\u8cbb\u8cc7\u6e90\u3002<\/p>\n<h2 id=\"%e5%9f%ba%e6%9c%ac%e6%9f%a5%e8%a9%a2%e8%aa%9e%e6%b3%95-rKmgZlmJIM\">\u57fa\u672c\u67e5\u8a62\u8a9e\u6cd5<\/h2>\n<p>\u8981\u67e5\u8a62\u91cd\u8907\u51fa\u73fe\u7684\u8a18\u9304\uff0c\u6211\u5011\u901a\u5e38\u4f7f\u7528 <code>GROUP BY<\/code> \u548c <code>HAVING<\/code> \u5b50\u53e5\u3002\u4ee5\u4e0b\u662f\u57fa\u672c\u7684\u67e5\u8a62\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>SELECT column_name, COUNT(*) as count\nFROM table_name\nGROUP BY column_name\nHAVING COUNT(*) &gt; 1;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c<code>column_name<\/code> \u662f\u6211\u5011\u8981\u6aa2\u67e5\u91cd\u8907\u7684\u5217\uff0c<code>table_name<\/code> \u662f\u6211\u5011\u7684\u6578\u64da\u8868\u3002\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u91cd\u8907\u7684\u8a18\u9304\u53ca\u5176\u51fa\u73fe\u7684\u6b21\u6578\u3002<\/p>\n<h2 id=\"%e7%af%84%e4%be%8b%ef%bc%9a%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e7%9a%84%e9%9b%bb%e5%ad%90%e9%83%b5%e4%bb%b6%e5%9c%b0%e5%9d%80-rKmgZlmJIM\">\u7bc4\u4f8b\uff1a\u67e5\u8a62\u91cd\u8907\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba <code>users<\/code> \u7684\u8868\uff0c\u5305\u542b\u7528\u6236\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u3002\u6211\u5011\u60f3\u8981\u627e\u51fa\u6240\u6709\u91cd\u8907\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u53ca\u5176\u51fa\u73fe\u6b21\u6578\u3002\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT email, COUNT(*) as count\nFROM users\nGROUP BY email\nHAVING COUNT(*) &gt; 1;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u91cd\u8907\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u53ca\u5176\u51fa\u73fe\u7684\u6b21\u6578\uff0c\u5e6b\u52a9\u6211\u5011\u8b58\u5225\u91cd\u8907\u7684\u7528\u6236\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e9%80%b2%e9%9a%8e%e6%9f%a5%e8%a9%a2%ef%bc%9a%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84%e7%9a%84%e5%85%b6%e4%bb%96%e4%bf%a1%e6%81%af-rKmgZlmJIM\">\u9032\u968e\u67e5\u8a62\uff1a\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u7684\u5176\u4ed6\u4fe1\u606f<\/h2>\n<p>\u5982\u679c\u6211\u5011\u5e0c\u671b\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u7684\u5176\u4ed6\u4fe1\u606f\uff0c\u4f8b\u5982\u7528\u6236\u7684\u540d\u7a31\u548c\u8a3b\u518a\u65e5\u671f\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT email, name, registration_date, COUNT(*) as count\nFROM users\nGROUP BY email, name, registration_date\nHAVING COUNT(*) &gt; 1;<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u67e5\u8a62\u5c07\u8fd4\u56de\u91cd\u8907\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u53ca\u5176\u5c0d\u61c9\u7684\u7528\u6236\u540d\u7a31\u548c\u8a3b\u518a\u65e5\u671f\uff0c\u63d0\u4f9b\u66f4\u5168\u9762\u7684\u6578\u64da\u5206\u6790\u3002<\/p>\n<h2 id=\"%e8%99%95%e7%90%86%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84-rKmgZlmJIM\">\u8655\u7406\u91cd\u8907\u8a18\u9304<\/h2>\n<p>\u5728\u8b58\u5225\u91cd\u8907\u8a18\u9304\u5f8c\uff0c\u4f01\u696d\u901a\u5e38\u9700\u8981\u6c7a\u5b9a\u5982\u4f55\u8655\u7406\u9019\u4e9b\u8a18\u9304\u3002\u5e38\u898b\u7684\u8655\u7406\u65b9\u6cd5\u5305\u62ec\uff1a<\/p>\n<ul>\n<li>\u522a\u9664\u91cd\u8907\u8a18\u9304\uff1a\u4fdd\u7559\u4e00\u689d\u8a18\u9304\uff0c\u522a\u9664\u5176\u4ed6\u91cd\u8907\u7684\u8a18\u9304\u3002<\/li>\n<li>\u5408\u4f75\u8a18\u9304\uff1a\u5c07\u91cd\u8907\u7684\u8a18\u9304\u5408\u4f75\u70ba\u4e00\u689d\uff0c\u4fdd\u7559\u6240\u6709\u91cd\u8981\u4fe1\u606f\u3002<\/li>\n<li>\u6a19\u8a18\u91cd\u8907\uff1a\u5728\u6578\u64da\u4e2d\u6a19\u8a18\u91cd\u8907\u7684\u8a18\u9304\uff0c\u4ee5\u4fbf\u5f8c\u7e8c\u8655\u7406\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-rKmgZlmJIM\">\u7e3d\u7d50<\/h2>\n<p>\u67e5\u8a62\u91cd\u8907\u51fa\u73fe\u6b21\u6578\u6700\u591a\u7684\u8a18\u9304\u662f\u6578\u64da\u5206\u6790\u4e2d\u7684\u4e00\u500b\u91cd\u8981\u6b65\u9a5f\u3002\u901a\u904e\u4f7f\u7528 MySQL \u7684 <code>GROUP BY<\/code> \u548c <code>HAVING<\/code> \u5b50\u53e5\uff0c\u6211\u5011\u53ef\u4ee5\u8f15\u9b06\u8b58\u5225\u548c\u8655\u7406\u91cd\u8907\u7684\u6578\u64da\u3002\u9019\u4e0d\u50c5\u6709\u52a9\u65bc\u63d0\u9ad8\u6578\u64da\u7684\u6e96\u78ba\u6027\uff0c\u9084\u80fd\u5e6b\u52a9\u4f01\u696d\u505a\u51fa\u66f4\u660e\u667a\u7684\u6c7a\u7b56\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u7a69\u5b9a\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u89e3\u6c7a\u65b9\u6848\u4f86\u652f\u6301\u60a8\u7684\u6578\u64da\u5eab\u7ba1\u7406\uff0cServer.HK \u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u4e0d\u540c\u9700\u6c42\u3002\u7121\u8ad6\u662f\u5c0f\u578b\u4f01\u696d\u9084\u662f\u5927\u578b\u4f01\u696d\uff0c\u6211\u5011\u7684 <a href=\"https:\/\/server.hk\">\u4e91\u670d\u52a1\u5668<\/a> \u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u53ef\u9760\u7684\u6027\u80fd\u548c\u5b89\u5168\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u4f7f\u7528 MySQL \u67e5\u8a62\u91cd\u8907\u51fa\u73fe\u6b21\u6578\u6700\u591a\u7684\u8a18\u9304\uff0c\u63d0\u5347\u6578\u64da\u5206\u6790\u6548\u7387\uff0c\u8f15\u9b06\u8b58\u5225\u95dc\u9375\u6578\u64da\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-75828","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75828","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=75828"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75828\/revisions"}],"predecessor-version":[{"id":75829,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75828\/revisions\/75829"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=75828"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=75828"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=75828"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}