{"id":186248,"date":"2024-11-11T04:20:28","date_gmt":"2024-11-10T20:20:28","guid":{"rendered":"https:\/\/server.hk\/cnblog\/186248\/"},"modified":"2024-11-11T04:20:29","modified_gmt":"2024-11-10T20:20:29","slug":"%e6%95%b8%e6%93%9a%e5%ba%ab%e6%9f%a5%e8%a9%a2%e6%8a%80%e5%b7%a7%e8%a6%96%e9%a0%bb%e6%95%99%e7%a8%8b%ef%bc%88%e6%95%b8%e6%93%9a%e5%ba%ab%e6%9f%a5%e8%a9%a2%e8%a6%96%e9%a0%bb%e8%ac%9b%e8%a7%a3%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/186248\/","title":{"rendered":"\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7\u8996\u983b\u6559\u7a0b\uff08\u6578\u64da\u5eab\u67e5\u8a62\u8996\u983b\u8b1b\u89e3\uff09"},"content":{"rendered":"<h1 id=\"%e6%95%b8%e6%93%9a%e5%ba%ab%e6%9f%a5%e8%a9%a2%e6%8a%80%e5%b7%a7%e8%a6%96%e9%a0%bb%e6%95%99%e7%a8%8b%ef%bc%88%e6%95%b8%e6%93%9a%e5%ba%ab%e6%9f%a5%e8%a9%a2%e8%a6%96%e9%a0%bb%e8%ac%9b%e8%a7%a3%ef%bc%89-tHObmeFjly\">\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7\u8996\u983b\u6559\u7a0b\uff08\u6578\u64da\u5eab\u67e5\u8a62\u8996\u983b\u8b1b\u89e3\uff09<\/h1>\n<p>\u5728\u7576\u4eca\u6578\u64da\u9a45\u52d5\u7684\u4e16\u754c\u4e2d\uff0c\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7\u5c0d\u65bc\u958b\u767c\u8005\u548c\u6578\u64da\u5206\u6790\u5e2b\u4f86\u8aaa\u81f3\u95dc\u91cd\u8981\u3002\u7121\u8ad6\u662f\u5f9e\u4e8b\u7db2\u7ad9\u958b\u767c\u3001\u61c9\u7528\u7a0b\u5f0f\u958b\u767c\uff0c\u9084\u662f\u6578\u64da\u5206\u6790\uff0c\u638c\u63e1\u6709\u6548\u7684\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7\u90fd\u80fd\u986f\u8457\u63d0\u9ad8\u5de5\u4f5c\u6548\u7387\u548c\u6578\u64da\u8655\u7406\u80fd\u529b\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u4e00\u4e9b\u57fa\u672c\u7684\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7\uff0c\u4e26\u63d0\u4f9b\u76f8\u95dc\u7684\u8996\u983b\u6559\u7a0b\u8cc7\u6e90\uff0c\u5e6b\u52a9\u8b80\u8005\u66f4\u6df1\u5165\u5730\u7406\u89e3\u9019\u4e00\u4e3b\u984c\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e6%95%b8%e6%93%9a%e5%ba%ab%e6%9f%a5%e8%a9%a2%ef%bc%9f-tHObmeFjly\">\u4ec0\u9ebc\u662f\u6578\u64da\u5eab\u67e5\u8a62\uff1f<\/h2>\n<p>\u6578\u64da\u5eab\u67e5\u8a62\u662f\u6307\u5411\u6578\u64da\u5eab\u767c\u9001\u8acb\u6c42\u4ee5\u6aa2\u7d22\u3001\u66f4\u65b0\u6216\u522a\u9664\u6578\u64da\u7684\u904e\u7a0b\u3002\u67e5\u8a62\u901a\u5e38\u4f7f\u7528\u7d50\u69cb\u5316\u67e5\u8a62\u8a9e\u8a00\uff08SQL\uff09\u4f86\u7de8\u5beb\u3002SQL\u662f\u4e00\u7a2e\u6a19\u6e96\u7684\u6578\u64da\u5eab\u67e5\u8a62\u8a9e\u8a00\uff0c\u80fd\u5920\u8b93\u7528\u6236\u4ee5\u7c21\u55ae\u7684\u8a9e\u6cd5\u8207\u6578\u64da\u5eab\u9032\u884c\u4ea4\u4e92\u3002<\/p>\n<h2 id=\"%e5%9f%ba%e6%9c%ac%e7%9a%84%e6%95%b8%e6%93%9a%e5%ba%ab%e6%9f%a5%e8%a9%a2%e6%8a%80%e5%b7%a7-tHObmeFjly\">\u57fa\u672c\u7684\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7<\/h2>\n<h3 id=\"1-%e4%bd%bf%e7%94%a8select%e8%aa%9e%e5%8f%a5-tHObmeFjly\">1. \u4f7f\u7528SELECT\u8a9e\u53e5<\/h3>\n<p>SELECT\u8a9e\u53e5\u662f\u6700\u57fa\u672c\u7684\u67e5\u8a62\u8a9e\u53e5\uff0c\u7528\u65bc\u5f9e\u6578\u64da\u5eab\u4e2d\u6aa2\u7d22\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT * FROM users WHERE age &gt; 18;<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5e74\u9f61\u5927\u65bc18\u6b72\u7684\u7528\u6236\u4fe1\u606f\u3002<\/p>\n<h3 id=\"2-%e9%81%8b%e7%94%a8where%e5%ad%90%e5%8f%a5%e9%81%8e%e6%bf%be%e6%95%b8%e6%93%9a-tHObmeFjly\">2. \u904b\u7528WHERE\u5b50\u53e5\u904e\u6ffe\u6578\u64da<\/h3>\n<p>WHERE\u5b50\u53e5\u53ef\u4ee5\u5e6b\u52a9\u7528\u6236\u6839\u64da\u7279\u5b9a\u689d\u4ef6\u904e\u6ffe\u67e5\u8a62\u7d50\u679c\u3002\u9019\u5c0d\u65bc\u8655\u7406\u5927\u91cf\u6578\u64da\u6642\u5c24\u70ba\u91cd\u8981\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT name, email FROM users WHERE country = 'Hong Kong';<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u50c5\u8fd4\u56de\u4f86\u81ea\u9999\u6e2f\u7684\u7528\u6236\u7684\u59d3\u540d\u548c\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u3002<\/p>\n<h3 id=\"3-%e4%bd%bf%e7%94%a8join%e8%aa%9e%e5%8f%a5%e5%90%88%e4%bd%b5%e6%95%b8%e6%93%9a-tHObmeFjly\">3. \u4f7f\u7528JOIN\u8a9e\u53e5\u5408\u4f75\u6578\u64da<\/h3>\n<p>\u5728\u591a\u500b\u8868\u4e4b\u9593\u9032\u884c\u67e5\u8a62\u6642\uff0cJOIN\u8a9e\u53e5\u53ef\u4ee5\u7528\u4f86\u5408\u4f75\u6578\u64da\u3002\u4f8b\u5982\uff0c\u5047\u8a2d\u6709\u5169\u500b\u8868\uff1ausers\u548corders\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528JOIN\u4f86\u7372\u53d6\u7528\u6236\u53ca\u5176\u8a02\u55ae\u7684\u4fe1\u606f\uff1a<\/p>\n<pre><code>SELECT users.name, orders.product FROM users\nJOIN orders ON users.id = orders.user_id;<\/code><\/pre>\n<h3 id=\"4-%e5%88%a9%e7%94%a8group-by%e5%92%8chaving%e9%80%b2%e8%a1%8c%e8%81%9a%e5%90%88%e6%9f%a5%e8%a9%a2-tHObmeFjly\">4. \u5229\u7528GROUP BY\u548cHAVING\u9032\u884c\u805a\u5408\u67e5\u8a62<\/h3>\n<p>GROUP BY\u5b50\u53e5\u53ef\u7528\u65bc\u5c07\u7d50\u679c\u96c6\u6309\u67d0\u4e00\u5217\u9032\u884c\u5206\u7d44\uff0c\u800cHAVING\u5b50\u53e5\u5247\u7528\u65bc\u904e\u6ffe\u805a\u5408\u7d50\u679c\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT country, COUNT(*) as user_count FROM users\nGROUP BY country HAVING user_count &gt; 10;<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u7528\u6236\u6578\u91cf\u8d85\u904e10\u7684\u570b\u5bb6\u53ca\u5176\u7528\u6236\u6578\u91cf\u3002<\/p>\n<h2 id=\"%e8%a6%96%e9%a0%bb%e6%95%99%e7%a8%8b%e8%b3%87%e6%ba%90-tHObmeFjly\">\u8996\u983b\u6559\u7a0b\u8cc7\u6e90<\/h2>\n<p>\u70ba\u4e86\u5e6b\u52a9\u8b80\u8005\u66f4\u597d\u5730\u638c\u63e1\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e9b\u63a8\u85a6\u7684\u8996\u983b\u6559\u7a0b\u8cc7\u6e90\uff1a<\/p>\n<ul>\n<li><a href=\"https:\/\/www.youtube.com\/watch?v=example1\" rel=\"nofollow noopener\" target=\"_blank\">SQL \u57fa\u790e\u5165\u9580<\/a><\/li>\n<li><a href=\"https:\/\/www.youtube.com\/watch?v=example2\" rel=\"nofollow noopener\" target=\"_blank\">\u9032\u968e SQL \u67e5\u8a62\u6280\u5de7<\/a><\/li>\n<li><a href=\"https:\/\/www.youtube.com\/watch?v=example3\" rel=\"nofollow noopener\" target=\"_blank\">\u6578\u64da\u5eab\u8a2d\u8a08\u8207\u6700\u4f73\u5be6\u8e10<\/a><\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-tHObmeFjly\">\u7d50\u8ad6<\/h2>\n<p>\u638c\u63e1\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7\u5c0d\u65bc\u4efb\u4f55\u5f9e\u4e8b\u6578\u64da\u76f8\u95dc\u5de5\u4f5c\u7684\u5c08\u696d\u4eba\u58eb\u4f86\u8aaa\u90fd\u662f\u4e00\u9805\u91cd\u8981\u7684\u6280\u80fd\u3002\u901a\u904e\u5b78\u7fd2\u548c\u5be6\u8e10\u4e0a\u8ff0\u6280\u5de7\uff0c\u60a8\u5c07\u80fd\u5920\u66f4\u6709\u6548\u5730\u8655\u7406\u548c\u5206\u6790\u6578\u64da\u3002\u82e5\u60a8\u9700\u8981\u9ad8\u6548\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u670d\u52d9\uff0c\u9019\u5c07\u70ba\u60a8\u7684\u6578\u64da\u8655\u7406\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u638c\u63e1\u6578\u64da\u5eab\u67e5\u8a62\u6280\u5de7\uff0c\u901a\u904e\u8996\u983b\u6559\u7a0b\u5b78\u7fd2\u9ad8\u6548\u67e5\u8a62\u65b9\u6cd5\uff0c\u63d0\u5347\u6578\u64da\u8655\u7406\u80fd\u529b\uff0c\u9069\u5408\u521d\u5b78\u8005\u8207\u9032\u968e\u7528\u6236\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-186248","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186248","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=186248"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186248\/revisions"}],"predecessor-version":[{"id":186249,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186248\/revisions\/186249"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=186248"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=186248"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=186248"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}