{"id":175239,"date":"2024-11-08T04:12:16","date_gmt":"2024-11-07T20:12:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/175239\/"},"modified":"2024-11-08T04:12:17","modified_gmt":"2024-11-07T20:12:17","slug":"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8lower%e5%87%bd%e6%95%b8%e6%9f%a5%e8%a9%a2%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84%e5%b0%8f%e5%af%ab%e6%95%b8%e6%93%9a%ef%bc%9f-lower%e6%95%b8%e6%93%9a","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/175239\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528lower\u51fd\u6578\u67e5\u8a62\u6578\u64da\u5eab\u4e2d\u7684\u5c0f\u5beb\u6578\u64da\uff1f (lower\u6578\u64da\u5eab)"},"content":{"rendered":"<h1 id=\"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8lower%e5%87%bd%e6%95%b8%e6%9f%a5%e8%a9%a2%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84%e5%b0%8f%e5%af%ab%e6%95%b8%e6%93%9a%ef%bc%9f-lower%e6%95%b8%e6%93%9a-UiyARsIYop\">\u5982\u4f55\u4f7f\u7528lower\u51fd\u6578\u67e5\u8a62\u6578\u64da\u5eab\u4e2d\u7684\u5c0f\u5beb\u6578\u64da\uff1f (lower\u6578\u64da\u5eab)<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u67e5\u8a62\u6578\u64da\u7684\u65b9\u5f0f\u591a\u7a2e\u591a\u6a23\uff0c\u5176\u4e2d\u4e00\u500b\u5e38\u898b\u7684\u9700\u6c42\u662f\u5c0d\u5927\u5c0f\u5beb\u4e0d\u654f\u611f\u7684\u67e5\u8a62\u3002\u9019\u6642\uff0c<code>LOWER<\/code> \u51fd\u6578\u4fbf\u6210\u70ba\u4e86\u4e00\u500b\u975e\u5e38\u6709\u7528\u7684\u5de5\u5177\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u5982\u4f55\u4f7f\u7528 <code>LOWER<\/code> \u51fd\u6578\u4f86\u67e5\u8a62\u6578\u64da\u5eab\u4e2d\u7684\u5c0f\u5beb\u6578\u64da\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u793a\u4f8b\u548c\u4ee3\u78bc\u7247\u6bb5\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%aflower%e5%87%bd%e6%95%b8%ef%bc%9f-UiyARsIYop\">\u4ec0\u9ebc\u662fLOWER\u51fd\u6578\uff1f<\/h2>\n<p><code>LOWER<\/code> \u51fd\u6578\u662f\u4e00\u500b SQL \u51fd\u6578\uff0c\u7528\u65bc\u5c07\u5b57\u7b26\u4e32\u8f49\u63db\u70ba\u5c0f\u5beb\u5b57\u6bcd\u3002\u9019\u5728\u9032\u884c\u67e5\u8a62\u6642\u7279\u5225\u6709\u7528\uff0c\u56e0\u70ba\u5b83\u53ef\u4ee5\u5e6b\u52a9\u6211\u5011\u5ffd\u7565\u5927\u5c0f\u5beb\u7684\u5dee\u7570\uff0c\u5f9e\u800c\u7372\u5f97\u66f4\u6e96\u78ba\u7684\u67e5\u8a62\u7d50\u679c\u3002<\/p>\n<h2 id=\"lower%e5%87%bd%e6%95%b8%e7%9a%84%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-UiyARsIYop\">LOWER\u51fd\u6578\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p>\u5728 SQL \u4e2d\uff0c<code>LOWER<\/code> \u51fd\u6578\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>LOWER(string)<\/code><\/pre>\n<p>\u5176\u4e2d\uff0c<code>string<\/code> \u662f\u8981\u8f49\u63db\u70ba\u5c0f\u5beb\u7684\u5b57\u7b26\u4e32\u3002\u9019\u500b\u51fd\u6578\u53ef\u4ee5\u7528\u65bc SELECT \u8a9e\u53e5\u3001WHERE \u5b50\u53e5\u7b49\u591a\u500b\u5730\u65b9\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8lower%e5%87%bd%e6%95%b8%e7%9a%84%e5%af%a6%e9%9a%9b%e7%a4%ba%e4%be%8b-UiyARsIYop\">\u4f7f\u7528LOWER\u51fd\u6578\u7684\u5be6\u969b\u793a\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u4e9b\u4f7f\u7528 <code>LOWER<\/code> \u51fd\u6578\u7684\u5be6\u969b\u793a\u4f8b\uff0c\u5e6b\u52a9\u60a8\u66f4\u597d\u5730\u7406\u89e3\u5176\u7528\u6cd5\u3002<\/p>\n<h3 id=\"%e7%a4%ba%e4%be%8b1%ef%bc%9a%e5%9f%ba%e6%9c%ac%e6%9f%a5%e8%a9%a2-UiyARsIYop\">\u793a\u4f8b1\uff1a\u57fa\u672c\u67e5\u8a62<\/h3>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba <code>users<\/code> \u7684\u8868\uff0c\u8a72\u8868\u5305\u542b\u7528\u6236\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u3002\u6211\u5011\u5e0c\u671b\u67e5\u8a62\u6240\u6709\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u70ba <code>example@domain.com<\/code> \u7684\u7528\u6236\uff0c\u7121\u8ad6\u5176\u5927\u5c0f\u5beb\u5982\u4f55\u3002\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT * FROM users WHERE LOWER(email) = LOWER('example@domain.com');<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c\u7121\u8ad6\u7528\u6236\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u662f <code>Example@Domain.com<\/code> \u9084\u662f <code>EXAMPLE@DOMAIN.COM<\/code>\uff0c\u90fd\u80fd\u6b63\u78ba\u5339\u914d\u3002<\/p>\n<h3 id=\"%e7%a4%ba%e4%be%8b2%ef%bc%9a%e4%bd%bf%e7%94%a8like%e9%81%8b%e7%ae%97%e7%ac%a6-UiyARsIYop\">\u793a\u4f8b2\uff1a\u4f7f\u7528LIKE\u904b\u7b97\u7b26<\/h3>\n<p>\u5982\u679c\u6211\u5011\u60f3\u67e5\u8a62\u6240\u6709\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u4e2d\u5305\u542b\u67d0\u500b\u7279\u5b9a\u5b57\u7b26\u4e32\u7684\u7528\u6236\uff0c\u53ef\u4ee5\u4f7f\u7528 <code>LIKE<\/code> \u904b\u7b97\u7b26\u7d50\u5408 <code>LOWER<\/code> \u51fd\u6578\u3002\u4f8b\u5982\uff0c\u67e5\u8a62\u6240\u6709\u5305\u542b <code>domain<\/code> \u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\uff1a<\/p>\n<pre><code>SELECT * FROM users WHERE LOWER(email) LIKE '%domain%';<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5305\u542b <code>domain<\/code> \u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\uff0c\u7121\u8ad6\u5176\u5927\u5c0f\u5beb\u5982\u4f55\u3002<\/p>\n<h3 id=\"%e7%a4%ba%e4%be%8b3%ef%bc%9a%e6%9b%b4%e6%96%b0%e6%95%b8%e6%93%9a-UiyARsIYop\">\u793a\u4f8b3\uff1a\u66f4\u65b0\u6578\u64da<\/h3>\n<p>\u9664\u4e86\u67e5\u8a62\uff0c<code>LOWER<\/code> \u51fd\u6578\u9084\u53ef\u4ee5\u7528\u65bc\u66f4\u65b0\u6578\u64da\u3002\u4f8b\u5982\uff0c\u5982\u679c\u6211\u5011\u5e0c\u671b\u5c07\u6240\u6709\u7528\u6236\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u7d71\u4e00\u8f49\u63db\u70ba\u5c0f\u5beb\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u8a9e\u53e5\uff1a<\/p>\n<pre><code>UPDATE users SET email = LOWER(email);<\/code><\/pre>\n<p>\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u6578\u64da\u5eab\u4e2d\u7684\u6240\u6709\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u90fd\u662f\u5c0f\u5beb\uff0c\u5f9e\u800c\u907f\u514d\u672a\u4f86\u67e5\u8a62\u6642\u7684\u5927\u5c0f\u5beb\u554f\u984c\u3002<\/p>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-UiyARsIYop\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u5728\u4f7f\u7528 <code>LOWER<\/code> \u51fd\u6578\u6642\uff0c\u6709\u5e7e\u9ede\u9700\u8981\u6ce8\u610f\uff1a<\/p>\n<ul>\n<li>\u6027\u80fd\uff1a\u5728\u5927\u578b\u6578\u64da\u96c6\u4e0a\u4f7f\u7528 <code>LOWER<\/code> \u51fd\u6578\u53ef\u80fd\u6703\u5f71\u97ff\u67e5\u8a62\u6027\u80fd\uff0c\u56e0\u70ba\u5b83\u9700\u8981\u5c0d\u6bcf\u4e00\u884c\u6578\u64da\u9032\u884c\u8655\u7406\u3002<\/li>\n<li>\u7d22\u5f15\uff1a\u5982\u679c\u5728\u67e5\u8a62\u4e2d\u4f7f\u7528 <code>LOWER<\/code> \u51fd\u6578\uff0c\u53ef\u80fd\u7121\u6cd5\u5229\u7528\u7d22\u5f15\uff0c\u5f9e\u800c\u5c0e\u81f4\u67e5\u8a62\u901f\u5ea6\u8b8a\u6162\u3002<\/li>\n<li>\u6578\u64da\u5b8c\u6574\u6027\uff1a\u5728\u66f4\u65b0\u6578\u64da\u6642\uff0c\u78ba\u4fdd\u4e0d\u6703\u4e1f\u5931\u539f\u59cb\u6578\u64da\u7684\u5927\u5c0f\u5beb\u4fe1\u606f\uff0c\u9664\u975e\u9019\u662f\u60a8\u7684\u9700\u6c42\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-UiyARsIYop\">\u7e3d\u7d50<\/h2>\n<p>\u4f7f\u7528 <code>LOWER<\/code> \u51fd\u6578\u67e5\u8a62\u6578\u64da\u5eab\u4e2d\u7684\u5c0f\u5beb\u6578\u64da\u662f\u4e00\u7a2e\u6709\u6548\u7684\u65b9\u6cd5\uff0c\u53ef\u4ee5\u5e6b\u52a9\u6211\u5011\u9032\u884c\u5927\u5c0f\u5beb\u4e0d\u654f\u611f\u7684\u67e5\u8a62\u3002\u901a\u904e\u4e0a\u8ff0\u793a\u4f8b\uff0c\u6211\u5011\u53ef\u4ee5\u770b\u5230\u5982\u4f55\u5728\u4e0d\u540c\u7684\u60c5\u6cc1\u4e0b\u4f7f\u7528\u9019\u500b\u51fd\u6578\u4f86\u7372\u53d6\u6240\u9700\u7684\u6578\u64da\u3002\u7121\u8ad6\u662f\u5728\u67e5\u8a62\u9084\u662f\u66f4\u65b0\u6578\u64da\u6642\uff0c<code>LOWER<\/code> \u51fd\u6578\u90fd\u80fd\u63d0\u4f9b\u4fbf\u5229\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK \u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u60a8\u7684\u9700\u6c42\u3002\u7121\u8ad6\u662f <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u9084\u662f\u5176\u4ed6\u985e\u578b\u7684 <a href=\"https:\/\/server.hk\">\u4f3a\u670d\u5668<\/a>\uff0c\u6211\u5011\u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u7684\u670d\u52d9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u4f7f\u7528lower\u51fd\u6578\u5728\u6578\u64da\u5eab\u4e2d\u67e5\u8a62\u5c0f\u5beb\u6578\u64da\uff0c\u63d0\u5347\u67e5\u8a62\u6548\u7387\uff0c\u78ba\u4fdd\u6578\u64da\u4e00\u81f4\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-175239","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175239","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=175239"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175239\/revisions"}],"predecessor-version":[{"id":175240,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175239\/revisions\/175240"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=175239"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=175239"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=175239"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}