{"id":76080,"date":"2024-10-16T03:41:15","date_gmt":"2024-10-15T19:41:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/76080\/"},"modified":"2024-10-16T03:41:15","modified_gmt":"2024-10-15T19:41:15","slug":"mysql%e8%81%af%e7%b5%90%e6%9f%a5%e8%a9%a2%e4%b8%80%e8%a6%bd","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/76080\/","title":{"rendered":"MySQL\u806f\u7d50\u67e5\u8a62\u4e00\u89bd"},"content":{"rendered":"<h1 id=\"mysql%e8%81%af%e7%b5%90%e6%9f%a5%e8%a9%a2%e4%b8%80%e8%a6%bd-xPnYeRcozx\">MySQL\u806f\u7d50\u67e5\u8a62\u4e00\u89bd<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u958b\u6e90\u6578\u64da\u5eab\uff0c\u7279\u5225\u662f\u5728Web\u61c9\u7528\u7a0b\u5e8f\u4e2d\u3002\u806f\u7d50\u67e5\u8a62\u662fMySQL\u4e2d\u4e00\u500b\u91cd\u8981\u7684\u529f\u80fd\uff0c\u80fd\u5920\u5c07\u591a\u500b\u8868\u4e2d\u7684\u6578\u64da\u9032\u884c\u6574\u5408\uff0c\u5f9e\u800c\u63d0\u4f9b\u66f4\u8c50\u5bcc\u7684\u4fe1\u606f\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eMySQL\u7684\u806f\u7d50\u67e5\u8a62\uff0c\u5305\u62ec\u5176\u985e\u578b\u3001\u7528\u6cd5\u53ca\u793a\u4f8b\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e8%81%af%e7%b5%90%e6%9f%a5%e8%a9%a2%ef%bc%9f-xPnYeRcozx\">\u4ec0\u9ebc\u662f\u806f\u7d50\u67e5\u8a62\uff1f<\/h2>\n<p>\u806f\u7d50\u67e5\u8a62\u662f\u6307\u5728SQL\u67e5\u8a62\u4e2d\uff0c\u901a\u904e\u67d0\u4e9b\u689d\u4ef6\u5c07\u5169\u500b\u6216\u591a\u500b\u8868\u7684\u6578\u64da\u9032\u884c\u7d44\u5408\u3002\u9019\u7a2e\u67e5\u8a62\u65b9\u5f0f\u4f7f\u5f97\u7528\u6236\u80fd\u5920\u5f9e\u4e0d\u540c\u7684\u8868\u4e2d\u63d0\u53d6\u76f8\u95dc\u6578\u64da\uff0c\u5f9e\u800c\u9032\u884c\u66f4\u8907\u96dc\u7684\u6578\u64da\u5206\u6790\u3002<\/p>\n<h2 id=\"%e8%81%af%e7%b5%90%e6%9f%a5%e8%a9%a2%e7%9a%84%e9%a1%9e%e5%9e%8b-xPnYeRcozx\">\u806f\u7d50\u67e5\u8a62\u7684\u985e\u578b<\/h2>\n<p>MySQL\u652f\u6301\u591a\u7a2e\u806f\u7d50\u67e5\u8a62\uff0c\u4e3b\u8981\u5305\u62ec\u4ee5\u4e0b\u5e7e\u7a2e\uff1a<\/p>\n<ul>\n<li><strong id=\"%e5%85%a7%e8%81%af%e7%b5%90%ef%bc%88inner-join%ef%bc%89-xPnYeRcozx\">\u5167\u806f\u7d50\uff08INNER JOIN\uff09<\/strong><\/li>\n<li><strong id=\"%e5%b7%a6%e8%81%af%e7%b5%90%ef%bc%88left-join%ef%bc%89-xPnYeRcozx\">\u5de6\u806f\u7d50\uff08LEFT JOIN\uff09<\/strong><\/li>\n<li><strong id=\"%e5%8f%b3%e8%81%af%e7%b5%90%ef%bc%88right-join%ef%bc%89-xPnYeRcozx\">\u53f3\u806f\u7d50\uff08RIGHT JOIN\uff09<\/strong><\/li>\n<li><strong id=\"%e5%85%a8%e8%81%af%e7%b5%90%ef%bc%88full-join%ef%bc%89-xPnYeRcozx\">\u5168\u806f\u7d50\uff08FULL JOIN\uff09<\/strong><\/li>\n<li><strong id=\"%e4%ba%a4%e5%8f%89%e8%81%af%e7%b5%90%ef%bc%88cross-join%ef%bc%89-xPnYeRcozx\">\u4ea4\u53c9\u806f\u7d50\uff08CROSS JOIN\uff09<\/strong><\/li>\n<\/ul>\n<h3 id=\"%e5%85%a7%e8%81%af%e7%b5%90%ef%bc%88inner-join%ef%bc%89-xPnYeRcozx\">\u5167\u806f\u7d50\uff08INNER JOIN\uff09<\/h3>\n<p>\u5167\u806f\u7d50\u662f\u6700\u5e38\u7528\u7684\u806f\u7d50\u985e\u578b\uff0c\u5b83\u53ea\u8fd4\u56de\u5728\u5169\u500b\u8868\u4e2d\u90fd\u6709\u7684\u8a18\u9304\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u5167\u806f\u7d50\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT a.name, b.order_date \nFROM customers a \nINNER JOIN orders b ON a.customer_id = b.customer_id;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c\u53ea\u6709\u90a3\u4e9b\u5728customers\u8868\u548corders\u8868\u4e2d\u90fd\u6709\u7684\u5ba2\u6236\u8a18\u9304\u6703\u88ab\u8fd4\u56de\u3002<\/p>\n<h3 id=\"%e5%b7%a6%e8%81%af%e7%b5%90%ef%bc%88left-join%ef%bc%89-xPnYeRcozx\">\u5de6\u806f\u7d50\uff08LEFT JOIN\uff09<\/h3>\n<p>\u5de6\u806f\u7d50\u8fd4\u56de\u5de6\u5074\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\uff0c\u5373\u4f7f\u53f3\u5074\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u8a18\u9304\u3002\u793a\u4f8b\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT a.name, b.order_date \nFROM customers a \nLEFT JOIN orders b ON a.customer_id = b.customer_id;<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u67e5\u8a62\u6703\u8fd4\u56de\u6240\u6709\u5ba2\u6236\u7684\u540d\u7a31\uff0c\u5373\u4f7f\u67d0\u4e9b\u5ba2\u6236\u6c92\u6709\u4e0b\u904e\u8a02\u55ae\u3002<\/p>\n<h3 id=\"%e5%8f%b3%e8%81%af%e7%b5%90%ef%bc%88right-join%ef%bc%89-xPnYeRcozx\">\u53f3\u806f\u7d50\uff08RIGHT JOIN\uff09<\/h3>\n<p>\u53f3\u806f\u7d50\u8207\u5de6\u806f\u7d50\u76f8\u53cd\uff0c\u5b83\u8fd4\u56de\u53f3\u5074\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u3002\u793a\u4f8b\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT a.name, b.order_date \nFROM customers a \nRIGHT JOIN orders b ON a.customer_id = b.customer_id;<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u67e5\u8a62\u6703\u8fd4\u56de\u6240\u6709\u8a02\u55ae\u7684\u65e5\u671f\uff0c\u5373\u4f7f\u67d0\u4e9b\u8a02\u55ae\u6c92\u6709\u5c0d\u61c9\u7684\u5ba2\u6236\u3002<\/p>\n<h3 id=\"%e5%85%a8%e8%81%af%e7%b5%90%ef%bc%88full-join%ef%bc%89-xPnYeRcozx\">\u5168\u806f\u7d50\uff08FULL JOIN\uff09<\/h3>\n<p>\u5168\u806f\u7d50\u8fd4\u56de\u5169\u500b\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\uff0c\u7121\u8ad6\u662f\u5426\u6709\u5339\u914d\u3002MySQL\u672c\u8eab\u4e0d\u76f4\u63a5\u652f\u6301\u5168\u806f\u7d50\uff0c\u4f46\u53ef\u4ee5\u901a\u904e\u7d44\u5408\u5de6\u806f\u7d50\u548c\u53f3\u806f\u7d50\u4f86\u5be6\u73fe\uff1a<\/p>\n<pre><code>SELECT a.name, b.order_date \nFROM customers a \nLEFT JOIN orders b ON a.customer_id = b.customer_id\nUNION\nSELECT a.name, b.order_date \nFROM customers a \nRIGHT JOIN orders b ON a.customer_id = b.customer_id;<\/code><\/pre>\n<h3 id=\"%e4%ba%a4%e5%8f%89%e8%81%af%e7%b5%90%ef%bc%88cross-join%ef%bc%89-xPnYeRcozx\">\u4ea4\u53c9\u806f\u7d50\uff08CROSS JOIN\uff09<\/h3>\n<p>\u4ea4\u53c9\u806f\u7d50\u8fd4\u56de\u5169\u500b\u8868\u7684\u7b1b\u5361\u723e\u7a4d\uff0c\u5373\u6bcf\u500b\u5de6\u5074\u8868\u7684\u8a18\u9304\u90fd\u6703\u8207\u53f3\u5074\u8868\u7684\u6bcf\u500b\u8a18\u9304\u9032\u884c\u7d44\u5408\u3002\u793a\u4f8b\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT a.name, b.product_name \nFROM customers a \nCROSS JOIN products b;<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u67e5\u8a62\u6703\u8fd4\u56de\u6bcf\u4f4d\u5ba2\u6236\u8207\u6bcf\u500b\u7522\u54c1\u7684\u7d44\u5408\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-xPnYeRcozx\">\u7e3d\u7d50<\/h2>\n<p>MySQL\u7684\u806f\u7d50\u67e5\u8a62\u529f\u80fd\u5f37\u5927\uff0c\u80fd\u5920\u5e6b\u52a9\u7528\u6236\u5f9e\u591a\u500b\u8868\u4e2d\u63d0\u53d6\u548c\u6574\u5408\u6578\u64da\u3002\u7121\u8ad6\u662f\u5167\u806f\u7d50\u3001\u5de6\u806f\u7d50\u3001\u53f3\u806f\u7d50\u3001\u5168\u806f\u7d50\u9084\u662f\u4ea4\u53c9\u806f\u7d50\uff0c\u6bcf\u7a2e\u806f\u7d50\u90fd\u6709\u5176\u7279\u5b9a\u7684\u7528\u9014\u548c\u5834\u666f\u3002\u4e86\u89e3\u9019\u4e9b\u806f\u7d50\u7684\u7528\u6cd5\uff0c\u80fd\u5920\u5e6b\u52a9\u958b\u767c\u8005\u66f4\u6709\u6548\u5730\u9032\u884c\u6578\u64da\u67e5\u8a62\u548c\u5206\u6790\u3002<\/p>\n<p>\u5982\u679c\u60a8\u9700\u8981\u7a69\u5b9a\u7684\u6578\u64da\u5eab\u652f\u6301\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u6216<a href=\"https:\/\/server.hk\">\u9999\u6e2f\u4f3a\u670d\u5668<\/a>\u4f86\u6258\u7ba1\u60a8\u7684MySQL\u6578\u64da\u5eab\uff0c\u78ba\u4fdd\u60a8\u7684\u61c9\u7528\u7a0b\u5e8f\u904b\u884c\u6d41\u66a2\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22MySQL\u806f\u7d50\u67e5\u8a62\u7684\u5168\u9762\u6307\u5357\uff0c\u4e86\u89e3\u4e0d\u540c\u985e\u578b\u7684\u806f\u7d50\u53ca\u5176\u7528\u6cd5\uff0c\u63d0\u5347\u6578\u64da\u5eab\u67e5\u8a62\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-76080","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76080","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=76080"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76080\/revisions"}],"predecessor-version":[{"id":76081,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76080\/revisions\/76081"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=76080"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=76080"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=76080"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}