{"id":180932,"date":"2024-11-09T14:23:18","date_gmt":"2024-11-09T06:23:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/180932\/"},"modified":"2024-11-09T14:23:19","modified_gmt":"2024-11-09T06:23:19","slug":"%e6%b7%b1%e5%85%a5%e4%ba%86%e8%a7%a3%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%97%e7%ac%a6%e4%b8%b2%e9%95%b7%e5%ba%a6%e5%87%bd%e6%95%b8-%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%97%e7%ac%a6%e4%b8%b2%e9%95%b7%e5%ba%a6","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/180932\/","title":{"rendered":"\u6df1\u5165\u4e86\u89e3\u6578\u64da\u5eab\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578 (\u6578\u64da\u5eab\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578)"},"content":{"rendered":"<h1 id=\"%e6%b7%b1%e5%85%a5%e4%ba%86%e8%a7%a3%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%97%e7%ac%a6%e4%b8%b2%e9%95%b7%e5%ba%a6%e5%87%bd%e6%95%b8-VCCkWYmcGb\">\u6df1\u5165\u4e86\u89e3\u6578\u64da\u5eab\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\u662f\u975e\u5e38\u91cd\u8981\u7684\u4e00\u500b\u6982\u5ff5\u3002\u7121\u8ad6\u662f\u5728\u6578\u64da\u9a57\u8b49\u3001\u6578\u64da\u8655\u7406\u9084\u662f\u6578\u64da\u5b58\u5132\u4e2d\uff0c\u4e86\u89e3\u5982\u4f55\u8a08\u7b97\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\u90fd\u80fd\u5e6b\u52a9\u958b\u767c\u8005\u66f4\u597d\u5730\u7ba1\u7406\u6578\u64da\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u6578\u64da\u5eab\u4e2d\u7684\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578\uff0c\u5305\u62ec\u5176\u7528\u9014\u3001\u4e0d\u540c\u6578\u64da\u5eab\u7cfb\u7d71\u4e2d\u7684\u5be6\u73fe\u65b9\u5f0f\u4ee5\u53ca\u4e00\u4e9b\u5be6\u969b\u7684\u61c9\u7528\u793a\u4f8b\u3002<\/p>\n<h2 id=\"%e5%ad%97%e7%ac%a6%e4%b8%b2%e9%95%b7%e5%ba%a6%e5%87%bd%e6%95%b8%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-VCCkWYmcGb\">\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578\u662f\u7528\u4f86\u8a08\u7b97\u5b57\u7b26\u4e32\u4e2d\u5b57\u7b26\u6578\u91cf\u7684\u51fd\u6578\u3002\u9019\u4e9b\u51fd\u6578\u901a\u5e38\u8fd4\u56de\u4e00\u500b\u6574\u6578\uff0c\u8868\u793a\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\u3002\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\u53ef\u4ee5\u5f71\u97ff\u6578\u64da\u7684\u5b58\u5132\u3001\u67e5\u8a62\u6027\u80fd\u4ee5\u53ca\u6578\u64da\u7684\u5b8c\u6574\u6027\u3002<\/p>\n<h2 id=\"%e4%b8%8d%e5%90%8c%e6%95%b8%e6%93%9a%e5%ba%ab%e7%b3%bb%e7%b5%b1%e4%b8%ad%e7%9a%84%e5%ad%97%e7%ac%a6%e4%b8%b2%e9%95%b7%e5%ba%a6%e5%87%bd%e6%95%b8-VCCkWYmcGb\">\u4e0d\u540c\u6578\u64da\u5eab\u7cfb\u7d71\u4e2d\u7684\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578<\/h2>\n<h3 id=\"1-mysql-VCCkWYmcGb\">1. MySQL<\/h3>\n<p>\u5728MySQL\u4e2d\uff0c\u8a08\u7b97\u5b57\u7b26\u4e32\u9577\u5ea6\u7684\u51fd\u6578\u662f <code>LENGTH()<\/code> \u548c <code>CHAR_LENGTH()<\/code>\u3002\u9019\u5169\u500b\u51fd\u6578\u7684\u5340\u5225\u5728\u65bc\uff1a<\/p>\n<ul>\n<li><code>LENGTH()<\/code> \u8fd4\u56de\u5b57\u7b26\u4e32\u7684\u5b57\u7bc0\u6578\u3002<\/li>\n<li><code>CHAR_LENGTH()<\/code> \u8fd4\u56de\u5b57\u7b26\u4e32\u7684\u5b57\u7b26\u6578\u3002<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT LENGTH('Hello'); -- \u8fd4\u56de 5\nSELECT CHAR_LENGTH('Hello'); -- \u8fd4\u56de 5\nSELECT LENGTH('\u4f60\u597d'); -- \u8fd4\u56de 6 (\u56e0\u70ba\u6bcf\u500b\u6f22\u5b57\u4f54\u75283\u500b\u5b57\u7bc0)\nSELECT CHAR_LENGTH('\u4f60\u597d'); -- \u8fd4\u56de 2<\/code><\/pre>\n<h3 id=\"2-postgresql-VCCkWYmcGb\">2. PostgreSQL<\/h3>\n<p>\u5728PostgreSQL\u4e2d\uff0c\u4f7f\u7528 <code>LENGTH()<\/code> \u51fd\u6578\u4f86\u8a08\u7b97\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\uff0c\u9019\u500b\u51fd\u6578\u8fd4\u56de\u7684\u662f\u5b57\u7b26\u6578\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT LENGTH('Hello'); -- \u8fd4\u56de 5\nSELECT LENGTH('\u4f60\u597d'); -- \u8fd4\u56de 2<\/code><\/pre>\n<h3 id=\"3-sql-server-VCCkWYmcGb\">3. SQL Server<\/h3>\n<p>\u5728SQL Server\u4e2d\uff0c\u4f7f\u7528 <code>LEN()<\/code> \u51fd\u6578\u4f86\u8a08\u7b97\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\u3002\u9019\u500b\u51fd\u6578\u6703\u5ffd\u7565\u5c3e\u90e8\u7684\u7a7a\u683c\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT LEN('Hello'); -- \u8fd4\u56de 5\nSELECT LEN('Hello   '); -- \u8fd4\u56de 5\nSELECT LEN('\u4f60\u597d'); -- \u8fd4\u56de 2<\/code><\/pre>\n<h3 id=\"4-oracle-VCCkWYmcGb\">4. Oracle<\/h3>\n<p>\u5728Oracle\u4e2d\uff0c\u4f7f\u7528 <code>LENGTH()<\/code> \u51fd\u6578\u4f86\u8a08\u7b97\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\uff0c\u9019\u500b\u51fd\u6578\u8fd4\u56de\u7684\u662f\u5b57\u7b26\u6578\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT LENGTH('Hello') FROM dual; -- \u8fd4\u56de 5\nSELECT LENGTH('\u4f60\u597d') FROM dual; -- \u8fd4\u56de 2<\/code><\/pre>\n<h2 id=\"%e5%ad%97%e7%ac%a6%e4%b8%b2%e9%95%b7%e5%ba%a6%e5%87%bd%e6%95%b8%e7%9a%84%e6%87%89%e7%94%a8%e5%a0%b4%e6%99%af-VCCkWYmcGb\">\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578\u7684\u61c9\u7528\u5834\u666f<\/h2>\n<p>\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578\u5728\u591a\u500b\u5834\u666f\u4e2d\u90fd\u975e\u5e38\u6709\u7528\uff0c\u5305\u62ec\u4f46\u4e0d\u9650\u65bc\uff1a<\/p>\n<ul>\n<li><strong>\u6578\u64da\u9a57\u8b49\uff1a<\/strong>\u5728\u63d2\u5165\u6216\u66f4\u65b0\u6578\u64da\u6642\uff0c\u53ef\u4ee5\u4f7f\u7528\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578\u4f86\u78ba\u4fdd\u6578\u64da\u7b26\u5408\u7279\u5b9a\u7684\u9577\u5ea6\u8981\u6c42\u3002<\/li>\n<li><strong>\u6578\u64da\u6e05\u7406\uff1a<\/strong>\u5728\u6578\u64da\u6e05\u7406\u904e\u7a0b\u4e2d\uff0c\u53ef\u4ee5\u6aa2\u67e5\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\uff0c\u4ee5\u4fbf\u522a\u9664\u4e0d\u7b26\u5408\u8981\u6c42\u7684\u6578\u64da\u3002<\/li>\n<li><strong>\u6027\u80fd\u512a\u5316\uff1a<\/strong>\u5728\u67e5\u8a62\u4e2d\uff0c\u53ef\u4ee5\u6839\u64da\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\u4f86\u512a\u5316\u7d22\u5f15\u548c\u67e5\u8a62\u6027\u80fd\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-VCCkWYmcGb\">\u7d50\u8ad6<\/h2>\n<p>\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\u626e\u6f14\u8457\u91cd\u8981\u7684\u89d2\u8272\uff0c\u7121\u8ad6\u662f\u5728\u6578\u64da\u9a57\u8b49\u3001\u6578\u64da\u8655\u7406\u9084\u662f\u6027\u80fd\u512a\u5316\u65b9\u9762\uff0c\u4e86\u89e3\u9019\u4e9b\u51fd\u6578\u7684\u4f7f\u7528\u65b9\u6cd5\u548c\u7279\u6027\u90fd\u662f\u975e\u5e38\u5fc5\u8981\u7684\u3002\u4e0d\u540c\u7684\u6578\u64da\u5eab\u7cfb\u7d71\u63d0\u4f9b\u4e86\u4e0d\u540c\u7684\u51fd\u6578\u4f86\u8a08\u7b97\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\uff0c\u958b\u767c\u8005\u61c9\u6839\u64da\u5177\u9ad4\u7684\u9700\u6c42\u9078\u64c7\u5408\u9069\u7684\u51fd\u6578\u4f86\u4f7f\u7528\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\u670d\u52d9\uff0c\u6211\u5011\u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6df1\u5165\u4e86\u89e3\u6578\u64da\u5eab\u5b57\u7b26\u4e32\u9577\u5ea6\u51fd\u6578\uff0c\u638c\u63e1\u5982\u4f55\u8a08\u7b97\u548c\u7ba1\u7406\u6578\u64da\u5eab\u4e2d\u5b57\u7b26\u4e32\u7684\u9577\u5ea6\uff0c\u63d0\u5347\u6578\u64da\u8655\u7406\u6548\u7387\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-180932","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/180932","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=180932"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/180932\/revisions"}],"predecessor-version":[{"id":180933,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/180932\/revisions\/180933"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=180932"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=180932"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=180932"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}