{"id":143763,"date":"2024-11-01T01:02:53","date_gmt":"2024-10-31T17:02:53","guid":{"rendered":"https:\/\/server.hk\/cnblog\/143763\/"},"modified":"2024-11-01T01:02:54","modified_gmt":"2024-10-31T17:02:54","slug":"sql-%e6%9f%a5%e8%a9%a2%e8%aa%9e%e5%8f%a5%ef%bc%9a%e5%8f%96-n-%e6%a2%9d%e6%95%b8%e6%93%9a%ef%bc%88%e6%80%8e%e6%a8%a3%e7%94%a8-sql-%e5%8f%96-n-%e6%a2%9d%e6%95%b8%e6%93%9a%e5%ba%ab%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/143763\/","title":{"rendered":"SQL \u67e5\u8a62\u8a9e\u53e5\uff1a\u53d6 n \u689d\u6578\u64da\uff08\u600e\u6a23\u7528 sql \u53d6 n \u689d\u6578\u64da\u5eab\uff09"},"content":{"rendered":"<h1 id=\"sql-%e6%9f%a5%e8%a9%a2%e8%aa%9e%e5%8f%a5%ef%bc%9a%e5%8f%96-n-%e6%a2%9d%e6%95%b8%e6%93%9a%ef%bc%88%e6%80%8e%e6%a8%a3%e7%94%a8-sql-%e5%8f%96-n-%e6%a2%9d%e6%95%b8%e6%93%9a%e5%ba%ab%ef%bc%89-LDYoFRATKM\">SQL \u67e5\u8a62\u8a9e\u53e5\uff1a\u53d6 n \u689d\u6578\u64da\uff08\u600e\u6a23\u7528 SQL \u53d6 n \u689d\u6578\u64da\u5eab\uff09<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0cSQL\uff08\u7d50\u69cb\u5316\u67e5\u8a62\u8a9e\u8a00\uff09\u662f\u4e00\u7a2e\u975e\u5e38\u91cd\u8981\u7684\u5de5\u5177\u3002\u7121\u8ad6\u662f\u5f9e\u5927\u578b\u4f01\u696d\u7684\u6578\u64da\u5eab\u4e2d\u63d0\u53d6\u4fe1\u606f\uff0c\u9084\u662f\u5f9e\u5c0f\u578b\u61c9\u7528\u7a0b\u5e8f\u4e2d\u7372\u53d6\u6578\u64da\uff0cSQL \u90fd\u80fd\u63d0\u4f9b\u5f37\u5927\u7684\u67e5\u8a62\u529f\u80fd\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u4f7f\u7528 SQL \u67e5\u8a62\u8a9e\u53e5\u4f86\u63d0\u53d6 n \u689d\u6578\u64da\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u793a\u4f8b\u548c\u6280\u5de7\u3002<\/p>\n<h2 id=\"%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-LDYoFRATKM\">\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>\u5728 SQL \u4e2d\uff0c\u67e5\u8a62\u8a9e\u53e5\u7684\u57fa\u672c\u7d50\u69cb\u662f\u4f7f\u7528 <code>SELECT<\/code> \u8a9e\u53e5\u4f86\u9078\u64c7\u6578\u64da\u3002\u8981\u63d0\u53d6\u7279\u5b9a\u6578\u91cf\u7684\u6578\u64da\uff0c\u6211\u5011\u901a\u5e38\u6703\u4f7f\u7528 <code>LIMIT<\/code> \u5b50\u53e5\u3002\u9019\u500b\u5b50\u53e5\u53ef\u4ee5\u9650\u5236\u67e5\u8a62\u7d50\u679c\u7684\u884c\u6578\uff0c\u5f9e\u800c\u4f7f\u6211\u5011\u80fd\u5920\u7372\u53d6\u6240\u9700\u7684 n \u689d\u6578\u64da\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8-limit-%e5%ad%90%e5%8f%a5-LDYoFRATKM\">\u4f7f\u7528 LIMIT \u5b50\u53e5<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4f7f\u7528 <code>LIMIT<\/code> \u5b50\u53e5\u7684\u57fa\u672c\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>SELECT column1, column2, ...\nFROM table_name\nWHERE condition\nLIMIT n;<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0c<code>n<\/code> \u662f\u60a8\u5e0c\u671b\u63d0\u53d6\u7684\u884c\u6578\u3002\u4f8b\u5982\uff0c\u5982\u679c\u60a8\u60f3\u5f9e\u540d\u70ba <code>employees<\/code> \u7684\u8868\u4e2d\u63d0\u53d6\u524d 5 \u689d\u6578\u64da\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT * FROM employees\nLIMIT 5;<\/code><\/pre>\n<h2 id=\"%e4%bd%bf%e7%94%a8-offset-%e5%ad%90%e5%8f%a5-LDYoFRATKM\">\u4f7f\u7528 OFFSET \u5b50\u53e5<\/h2>\n<p>\u9664\u4e86 <code>LIMIT<\/code>\uff0c\u60a8\u9084\u53ef\u4ee5\u4f7f\u7528 <code>OFFSET<\/code> \u5b50\u53e5\u4f86\u63a7\u5236\u5f9e\u54ea\u4e00\u884c\u958b\u59cb\u63d0\u53d6\u6578\u64da\u3002\u9019\u5728\u9700\u8981\u5206\u9801\u986f\u793a\u6578\u64da\u6642\u7279\u5225\u6709\u7528\u3002\u4ee5\u4e0b\u662f\u4f7f\u7528 <code>OFFSET<\/code> \u7684\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>SELECT column1, column2, ...\nFROM table_name\nWHERE condition\nLIMIT n OFFSET m;<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0c<code>m<\/code> \u662f\u60a8\u5e0c\u671b\u8df3\u904e\u7684\u884c\u6578\u3002\u4f8b\u5982\uff0c\u5982\u679c\u60a8\u60f3\u5f9e <code>employees<\/code> \u8868\u4e2d\u63d0\u53d6\u7b2c 6 \u5230\u7b2c 10 \u689d\u6578\u64da\uff0c\u53ef\u4ee5\u9019\u6a23\u5beb\uff1a<\/p>\n<pre><code>SELECT * FROM employees\nLIMIT 5 OFFSET 5;<\/code><\/pre>\n<h2 id=\"%e4%bd%bf%e7%94%a8-order-by-%e5%ad%90%e5%8f%a5-LDYoFRATKM\">\u4f7f\u7528 ORDER BY \u5b50\u53e5<\/h2>\n<p>\u5728\u63d0\u53d6 n \u689d\u6578\u64da\u6642\uff0c\u901a\u5e38\u9700\u8981\u5c0d\u7d50\u679c\u9032\u884c\u6392\u5e8f\u3002\u9019\u53ef\u4ee5\u901a\u904e <code>ORDER BY<\/code> \u5b50\u53e5\u4f86\u5be6\u73fe\u3002\u4ee5\u4e0b\u662f\u7d50\u5408 <code>ORDER BY<\/code> \u548c <code>LIMIT<\/code> \u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT * FROM employees\nORDER BY hire_date DESC\nLIMIT 5;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6700\u8fd1\u8058\u7528\u7684 5 \u540d\u54e1\u5de5\u3002<\/p>\n<h2 id=\"%e5%af%a6%e9%9a%9b%e6%87%89%e7%94%a8%e7%a4%ba%e4%be%8b-LDYoFRATKM\">\u5be6\u969b\u61c9\u7528\u793a\u4f8b<\/h2>\n<p>\u5047\u8a2d\u60a8\u6709\u4e00\u500b\u540d\u70ba <code>products<\/code> \u7684\u8868\uff0c\u4e26\u5e0c\u671b\u63d0\u53d6\u50f9\u683c\u6700\u4f4e\u7684 10 \u7a2e\u7522\u54c1\u3002\u60a8\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT * FROM products\nORDER BY price ASC\nLIMIT 10;<\/code><\/pre>\n<p>\u9019\u6a23\uff0c\u60a8\u5c07\u7372\u5f97\u50f9\u683c\u6700\u4f4e\u7684 10 \u7a2e\u7522\u54c1\u7684\u5217\u8868\u3002<\/p>\n<h2 id=\"%e5%b0%8f%e7%b5%90-LDYoFRATKM\">\u5c0f\u7d50<\/h2>\n<p>\u4f7f\u7528 SQL \u67e5\u8a62\u8a9e\u53e5\u63d0\u53d6 n \u689d\u6578\u64da\u662f\u4e00\u500b\u57fa\u672c\u4f46\u91cd\u8981\u7684\u6280\u80fd\u3002\u901a\u904e\u7d50\u5408 <code>LIMIT<\/code>\u3001<code>OFFSET<\/code> \u548c <code>ORDER BY<\/code> \u5b50\u53e5\uff0c\u60a8\u53ef\u4ee5\u9748\u6d3b\u5730\u63a7\u5236\u67e5\u8a62\u7d50\u679c\uff0c\u6eff\u8db3\u4e0d\u540c\u7684\u9700\u6c42\u3002\u7121\u8ad6\u662f\u5728\u6578\u64da\u5206\u6790\u3001\u5831\u544a\u751f\u6210\u9084\u662f\u61c9\u7528\u7a0b\u5e8f\u958b\u767c\u4e2d\uff0c\u9019\u4e9b\u6280\u5de7\u90fd\u80fd\u5e6b\u52a9\u60a8\u66f4\u6709\u6548\u5730\u7ba1\u7406\u548c\u5229\u7528\u6578\u64da\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u548c\u67e5\u8a62\u6709\u9032\u4e00\u6b65\u7684\u9700\u6c42\uff0c\u8003\u616e\u4f7f\u7528 <a href=\"https:\/\/server.hk\">\u9999\u6e2f VPS<\/a> \u670d\u52d9\u4f86\u642d\u5efa\u60a8\u7684\u6578\u64da\u5eab\u74b0\u5883\uff0c\u4eab\u53d7\u66f4\u9ad8\u7684\u6027\u80fd\u548c\u7a69\u5b9a\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u4f7f\u7528 SQL \u67e5\u8a62\u8a9e\u53e5\u5f9e\u6578\u64da\u5eab\u4e2d\u63d0\u53d6 n \u689d\u6578\u64da\uff0c\u638c\u63e1\u6709\u6548\u7684\u6578\u64da\u6aa2\u7d22\u6280\u5de7\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-143763","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143763","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=143763"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143763\/revisions"}],"predecessor-version":[{"id":143764,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143763\/revisions\/143764"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=143763"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=143763"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=143763"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}