{"id":79638,"date":"2024-10-16T13:25:39","date_gmt":"2024-10-16T05:25:39","guid":{"rendered":"https:\/\/server.hk\/cnblog\/79638\/"},"modified":"2024-10-16T13:25:39","modified_gmt":"2024-10-16T05:25:39","slug":"mysql%e6%8c%87%e4%bb%a4-second%ef%bc%88%e7%a7%92%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/79638\/","title":{"rendered":"MySQL\u6307\u4ee4: SECOND()\uff08\u79d2\uff09"},"content":{"rendered":"<h1 id=\"mysql%e6%8c%87%e4%bb%a4-second%ef%bc%88%e7%a7%92%ef%bc%89-IngUJcniEC\">MySQL\u6307\u4ee4: SECOND()\uff08\u79d2\uff09<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u958b\u6e90\u8cc7\u6599\u5eab\uff0c\u63d0\u4f9b\u4e86\u591a\u7a2e\u529f\u80fd\u4f86\u8655\u7406\u548c\u67e5\u8a62\u6578\u64da\u3002\u7576\u6d89\u53ca\u5230\u6642\u9593\u548c\u65e5\u671f\u7684\u64cd\u4f5c\u6642\uff0cMySQL\u63d0\u4f9b\u4e86\u591a\u500b\u51fd\u6578\u4f86\u5e6b\u52a9\u7528\u6236\u63d0\u53d6\u548c\u64cd\u4f5c\u6642\u9593\u6578\u64da\u3002\u5176\u4e2d\uff0c<code>SECOND()<\/code>\u51fd\u6578\u662f\u4e00\u500b\u975e\u5e38\u5be6\u7528\u7684\u5de5\u5177\uff0c\u80fd\u5920\u5f9e\u6642\u9593\u6216\u65e5\u671f\u6642\u9593\u503c\u4e2d\u63d0\u53d6\u51fa\u79d2\u6578\u3002<\/p>\n<h2 id=\"second%e5%87%bd%e6%95%b8%e7%9a%84%e5%9f%ba%e6%9c%ac%e7%94%a8%e6%b3%95-IngUJcniEC\">SECOND()\u51fd\u6578\u7684\u57fa\u672c\u7528\u6cd5<\/h2>\n<p><code>SECOND()<\/code>\u51fd\u6578\u7684\u8a9e\u6cd5\u975e\u5e38\u7c21\u55ae\uff0c\u4f7f\u7528\u65b9\u5f0f\u5982\u4e0b\uff1a<\/p>\n<pre><code>SECOND(time_value)<\/code><\/pre>\n<p>\u9019\u88e1\u7684<code>time_value<\/code>\u53ef\u4ee5\u662f\u6642\u9593\u683c\u5f0f\uff08\u5982<code>'HH:MM:SS'<\/code>\uff09\u6216\u65e5\u671f\u6642\u9593\u683c\u5f0f\uff08\u5982<code>'YYYY-MM-DD HH:MM:SS'<\/code>\uff09\u3002\u8a72\u51fd\u6578\u5c07\u8fd4\u56de\u4e00\u500b\u6574\u6578\uff0c\u8868\u793a\u8a72\u6642\u9593\u503c\u4e2d\u7684\u79d2\u6578\u3002<\/p>\n<h2 id=\"%e7%af%84%e4%be%8b-IngUJcniEC\">\u7bc4\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u4e9b\u4f7f\u7528<code>SECOND()<\/code>\u51fd\u6578\u7684\u7bc4\u4f8b\uff1a<\/p>\n<h3 id=\"%e7%af%84%e4%be%8b1-%e6%8f%90%e5%8f%96%e6%99%82%e9%96%93%e4%b8%ad%e7%9a%84%e7%a7%92%e6%95%b8-IngUJcniEC\">\u7bc4\u4f8b1: \u63d0\u53d6\u6642\u9593\u4e2d\u7684\u79d2\u6578<\/h3>\n<pre><code>SELECT SECOND('12:34:56') AS \u79d2\u6578;<\/code><\/pre>\n<p>\u57f7\u884c\u4e0a\u8ff0\u67e5\u8a62\u5f8c\uff0c\u7d50\u679c\u5c07\u986f\u793a\uff1a<\/p>\n<pre><code>\u79d2\u6578\n----------\n56\n<\/code><\/pre>\n<h3 id=\"%e7%af%84%e4%be%8b2-%e6%8f%90%e5%8f%96%e6%97%a5%e6%9c%9f%e6%99%82%e9%96%93%e4%b8%ad%e7%9a%84%e7%a7%92%e6%95%b8-IngUJcniEC\">\u7bc4\u4f8b2: \u63d0\u53d6\u65e5\u671f\u6642\u9593\u4e2d\u7684\u79d2\u6578<\/h3>\n<pre><code>SELECT SECOND('2023-10-01 15:45:30') AS \u79d2\u6578;<\/code><\/pre>\n<p>\u57f7\u884c\u5f8c\u7684\u7d50\u679c\u5c07\u662f\uff1a<\/p>\n<pre><code>\u79d2\u6578\n----------\n30\n<\/code><\/pre>\n<h2 id=\"%e5%9c%a8%e6%9f%a5%e8%a9%a2%e4%b8%ad%e7%9a%84%e6%87%89%e7%94%a8-IngUJcniEC\">\u5728\u67e5\u8a62\u4e2d\u7684\u61c9\u7528<\/h2>\n<p>\u5728\u5be6\u969b\u61c9\u7528\u4e2d\uff0c<code>SECOND()<\/code>\u51fd\u6578\u53ef\u4ee5\u8207\u5176\u4ed6\u67e5\u8a62\u689d\u4ef6\u7d50\u5408\u4f7f\u7528\u3002\u4f8b\u5982\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba<code>events<\/code>\u7684\u8868\u683c\uff0c\u8a72\u8868\u683c\u5305\u542b\u4e8b\u4ef6\u7684\u958b\u59cb\u6642\u9593\uff0c\u6211\u5011\u53ef\u4ee5\u4f7f\u7528<code>SECOND()<\/code>\u4f86\u7be9\u9078\u51fa\u7279\u5b9a\u79d2\u6578\u7684\u4e8b\u4ef6\uff1a<\/p>\n<pre><code>SELECT * FROM events WHERE SECOND(start_time) = 30;<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5728\u958b\u59cb\u6642\u9593\u7684\u79d2\u6578\u70ba30\u7684\u4e8b\u4ef6\u3002<\/p>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-IngUJcniEC\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u4f7f\u7528<code>SECOND()<\/code>\u51fd\u6578\u6642\uff0c\u6709\u5e7e\u9ede\u9700\u8981\u6ce8\u610f\uff1a<\/p>\n<ul>\n<li>\u5982\u679c\u50b3\u5165\u7684<code>time_value<\/code>\u70ba<code>NULL<\/code>\uff0c\u5247\u51fd\u6578\u5c07\u8fd4\u56de<code>NULL<\/code>\u3002<\/li>\n<li>\u8a72\u51fd\u6578\u50c5\u9069\u7528\u65bc\u6642\u9593\u548c\u65e5\u671f\u6642\u9593\u683c\u5f0f\uff0c\u5c0d\u65bc\u5176\u4ed6\u683c\u5f0f\u7684\u6578\u64da\uff0c\u53ef\u80fd\u6703\u5c0e\u81f4\u932f\u8aa4\u3002<\/li>\n<li>\u5728\u9032\u884c\u5927\u91cf\u6578\u64da\u67e5\u8a62\u6642\uff0c\u4f7f\u7528<code>SECOND()<\/code>\u53ef\u80fd\u6703\u5f71\u97ff\u6027\u80fd\uff0c\u7279\u5225\u662f\u5728\u5927\u578b\u6578\u64da\u96c6\u4e0a\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-IngUJcniEC\">\u7d50\u8ad6<\/h2>\n<p>MySQL\u7684<code>SECOND()<\/code>\u51fd\u6578\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u80fd\u5920\u5e6b\u52a9\u7528\u6236\u8f15\u9b06\u63d0\u53d6\u6642\u9593\u6216\u65e5\u671f\u6642\u9593\u4e2d\u7684\u79d2\u6578\u3002\u7121\u8ad6\u662f\u5728\u6578\u64da\u5206\u6790\u9084\u662f\u65e5\u5e38\u67e5\u8a62\u4e2d\uff0c\u9019\u500b\u51fd\u6578\u90fd\u80fd\u63d0\u4f9b\u4fbf\u5229\u3002\u900f\u904e\u6b63\u78ba\u7684\u4f7f\u7528\u65b9\u6cd5\u548c\u7bc4\u4f8b\uff0c\u958b\u767c\u8005\u53ef\u4ee5\u66f4\u6709\u6548\u5730\u8655\u7406\u6642\u9593\u6578\u64da\uff0c\u63d0\u5347\u6578\u64da\u5eab\u64cd\u4f5c\u7684\u6548\u7387\u3002<\/p>\n<p>\u5982\u9700\u9032\u4e00\u6b65\u4e86\u89e3MySQL\u53ca\u5176\u76f8\u95dc\u6280\u8853\uff0c\u60a8\u53ef\u4ee5\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u4f86\u642d\u5efa\u60a8\u7684\u958b\u767c\u74b0\u5883\uff0c\u4eab\u53d7\u7a69\u5b9a\u7684\u6027\u80fd\u548c\u9748\u6d3b\u7684\u914d\u7f6e\u9078\u64c7\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3MySQL\u6307\u4ee4SECOND()\uff0c\u7528\u4e8e\u63d0\u53d6\u65f6\u95f4\u503c\u4e2d\u7684\u79d2\u6570\uff0c\u7b80\u5316\u65f6\u95f4\u6570\u636e\u5904\u7406\u4e0e\u5206\u6790\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-79638","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/79638","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=79638"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/79638\/revisions"}],"predecessor-version":[{"id":79639,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/79638\/revisions\/79639"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=79638"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=79638"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=79638"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}