{"id":76208,"date":"2024-10-16T04:45:17","date_gmt":"2024-10-15T20:45:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/76208\/"},"modified":"2024-10-16T04:45:17","modified_gmt":"2024-10-15T20:45:17","slug":"mysql%e5%85%a5%e9%96%80%ef%bc%9a%e4%bd%bf%e7%94%a8cross-join%e7%94%9f%e6%88%90%e4%b8%80%e5%80%8b%e7%b5%90%e6%9e%9c%e9%9b%86%ef%bc%8c%e5%85%b6%e8%a1%8c%e6%95%b8%e7%ad%89%e6%96%bc%e7%ac%ac%e4%b8%80","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/76208\/","title":{"rendered":"MySQL\u5165\u9580\uff1a\u4f7f\u7528CROSS JOIN\u751f\u6210\u4e00\u500b\u7d50\u679c\u96c6\uff0c\u5176\u884c\u6578\u7b49\u65bc\u7b2c\u4e00\u500b\u8868\u7684\u884c\u6578\u4e58\u4ee5\u7b2c\u4e8c\u500b\u8868\u7684\u884c\u6578\u3002"},"content":{"rendered":"<h1 id=\"mysql%e5%85%a5%e9%96%80%ef%bc%9a%e4%bd%bf%e7%94%a8cross-join%e7%94%9f%e6%88%90%e4%b8%80%e5%80%8b%e7%b5%90%e6%9e%9c%e9%9b%86%ef%bc%8c%e5%85%b6%e8%a1%8c%e6%95%b8%e7%ad%89%e6%96%bc%e7%ac%ac%e4%b8%80-upTMMNWeFw\">MySQL\u5165\u9580\uff1a\u4f7f\u7528CROSS JOIN\u751f\u6210\u4e00\u500b\u7d50\u679c\u96c6\uff0c\u5176\u884c\u6578\u7b49\u65bc\u7b2c\u4e00\u500b\u8868\u7684\u884c\u6578\u4e58\u4ee5\u7b2c\u4e8c\u500b\u8868\u7684\u884c\u6578<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u975e\u5e38\u6d41\u884c\u7684\u9078\u64c7\uff0c\u56e0\u70ba\u5b83\u7684\u9748\u6d3b\u6027\u548c\u5f37\u5927\u7684\u529f\u80fd\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u5982\u4f55\u4f7f\u7528CROSS JOIN\u4f86\u751f\u6210\u4e00\u500b\u7d50\u679c\u96c6\uff0c\u5176\u884c\u6578\u7b49\u65bc\u7b2c\u4e00\u500b\u8868\u7684\u884c\u6578\u4e58\u4ee5\u7b2c\u4e8c\u500b\u8868\u7684\u884c\u6578\u3002\u9019\u7a2e\u64cd\u4f5c\u5728\u6578\u64da\u5206\u6790\u548c\u5831\u544a\u751f\u6210\u4e2d\u975e\u5e38\u6709\u7528\u3002<\/p>\n<h2 id=\"cross-join%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-upTMMNWeFw\">CROSS JOIN\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>CROSS JOIN\u662f\u4e00\u7a2e\u9023\u63a5\u64cd\u4f5c\uff0c\u6703\u8fd4\u56de\u5169\u500b\u8868\u4e2d\u6240\u6709\u53ef\u80fd\u7684\u884c\u7d44\u5408\u3002\u9019\u610f\u5473\u8457\uff0c\u5982\u679c\u7b2c\u4e00\u500b\u8868\u6709m\u884c\uff0c\u7b2c\u4e8c\u500b\u8868\u6709n\u884c\uff0c\u5247CROSS JOIN\u7684\u7d50\u679c\u96c6\u5c07\u5305\u542bm*n\u884c\u3002\u9019\u7a2e\u9023\u63a5\u65b9\u5f0f\u4e0d\u9700\u8981\u4efb\u4f55\u689d\u4ef6\uff0c\u56e0\u70ba\u5b83\u6703\u751f\u6210\u6240\u6709\u7684\u7d44\u5408\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8cross-join%e7%9a%84%e8%aa%9e%e6%b3%95-upTMMNWeFw\">\u4f7f\u7528CROSS JOIN\u7684\u8a9e\u6cd5<\/h2>\n<p>\u5728MySQL\u4e2d\uff0cCROSS JOIN\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT * FROM \u88681 CROSS JOIN \u88682;<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u8fd4\u56de\u88681\u548c\u88682\u7684\u6240\u6709\u884c\u7d44\u5408\u3002\u63a5\u4e0b\u4f86\uff0c\u6211\u5011\u5c07\u901a\u904e\u4e00\u500b\u5177\u9ad4\u7684\u4f8b\u5b50\u4f86\u6f14\u793a\u5982\u4f55\u4f7f\u7528CROSS JOIN\u3002<\/p>\n<h2 id=\"%e5%af%a6%e9%9a%9b%e7%af%84%e4%be%8b-upTMMNWeFw\">\u5be6\u969b\u7bc4\u4f8b<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u5169\u500b\u8868\uff1a<strong>products<\/strong>\u548c<strong>categories<\/strong>\u3002<\/p>\n<ul>\n<li><strong>products<\/strong>\u8868\uff1a<\/li>\n<pre><code>+----+------------+\n| id | name       |\n+----+------------+\n| 1  | Product A  |\n| 2  | Product B  |\n| 3  | Product C  |\n+----+------------+<\/code><\/pre>\n<li><strong>categories<\/strong>\u8868\uff1a<\/li>\n<pre><code>+----+-------------+\n| id | category    |\n+----+-------------+\n| 1  | Category 1  |\n| 2  | Category 2  |\n+----+-------------+<\/code><\/pre>\n<\/ul>\n<p>\u73fe\u5728\uff0c\u6211\u5011\u60f3\u8981\u751f\u6210\u4e00\u500b\u7d50\u679c\u96c6\uff0c\u986f\u793a\u6bcf\u500b\u7522\u54c1\u8207\u6bcf\u500b\u985e\u5225\u7684\u7d44\u5408\u3002\u6211\u5011\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0bSQL\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT products.name, categories.category\nFROM products\nCROSS JOIN categories;<\/code><\/pre>\n<p>\u57f7\u884c\u9019\u689d\u67e5\u8a62\u5f8c\uff0c\u6211\u5011\u5c07\u5f97\u5230\u4ee5\u4e0b\u7d50\u679c\uff1a<\/p>\n<pre><code>+------------+-------------+\n| name       | category    |\n+------------+-------------+\n| Product A  | Category 1  |\n| Product A  | Category 2  |\n| Product B  | Category 1  |\n| Product B  | Category 2  |\n| Product C  | Category 1  |\n| Product C  | Category 2  |\n+------------+-------------+<\/code><\/pre>\n<p>\u5982\u4e0a\u6240\u793a\uff0c\u7d50\u679c\u96c6\u7684\u884c\u6578\u70ba3\uff08\u7522\u54c1\u6578\u91cf\uff09\u4e58\u4ee52\uff08\u985e\u5225\u6578\u91cf\uff09\uff0c\u7e3d\u5171\u70ba6\u884c\u3002<\/p>\n<h2 id=\"cross-join%e7%9a%84%e6%87%89%e7%94%a8%e5%a0%b4%e6%99%af-upTMMNWeFw\">CROSS JOIN\u7684\u61c9\u7528\u5834\u666f<\/h2>\n<p>CROSS JOIN\u5728\u8a31\u591a\u5834\u666f\u4e2d\u90fd\u975e\u5e38\u6709\u7528\uff0c\u4f8b\u5982\uff1a<\/p>\n<ul>\n<li>\u751f\u6210\u5831\u544a\uff1a\u7576\u9700\u8981\u5c07\u6240\u6709\u53ef\u80fd\u7684\u7d44\u5408\u986f\u793a\u5728\u5831\u544a\u4e2d\u6642\uff0cCROSS JOIN\u53ef\u4ee5\u5e6b\u52a9\u751f\u6210\u5b8c\u6574\u7684\u6578\u64da\u96c6\u3002<\/li>\n<li>\u6578\u64da\u5206\u6790\uff1a\u5728\u9032\u884c\u6578\u64da\u5206\u6790\u6642\uff0c\u53ef\u80fd\u9700\u8981\u6bd4\u8f03\u4e0d\u540c\u985e\u5225\u6216\u7522\u54c1\u4e4b\u9593\u7684\u95dc\u4fc2\uff0cCROSS JOIN\u53ef\u4ee5\u63d0\u4f9b\u9019\u4e9b\u6578\u64da\u3002<\/li>\n<li>\u6e2c\u8a66\u6578\u64da\u751f\u6210\uff1a\u5728\u958b\u767c\u548c\u6e2c\u8a66\u968e\u6bb5\uff0cCROSS JOIN\u53ef\u4ee5\u7528\u4f86\u751f\u6210\u6e2c\u8a66\u6578\u64da\u96c6\u3002<\/li>\n<\/ul>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-upTMMNWeFw\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u96d6\u7136CROSS JOIN\u975e\u5e38\u5f37\u5927\uff0c\u4f46\u5728\u4f7f\u7528\u6642\u9700\u8981\u8b39\u614e\u3002\u7531\u65bc\u5b83\u6703\u751f\u6210\u6240\u6709\u53ef\u80fd\u7684\u884c\u7d44\u5408\uff0c\u7576\u5169\u500b\u8868\u7684\u884c\u6578\u90fd\u5f88\u5927\u6642\uff0c\u7d50\u679c\u96c6\u7684\u5927\u5c0f\u53ef\u80fd\u6703\u8fc5\u901f\u589e\u9577\uff0c\u5c0e\u81f4\u6027\u80fd\u554f\u984c\u3002\u56e0\u6b64\uff0c\u5728\u4f7f\u7528CROSS JOIN\u6642\uff0c\u5efa\u8b70\u5148\u8a55\u4f30\u6578\u64da\u91cf\uff0c\u4ee5\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u8cc7\u6e90\u6d88\u8017\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-upTMMNWeFw\">\u7e3d\u7d50<\/h2>\n<p>\u672c\u6587\u4ecb\u7d39\u4e86\u5982\u4f55\u4f7f\u7528CROSS JOIN\u751f\u6210\u4e00\u500b\u7d50\u679c\u96c6\uff0c\u5176\u884c\u6578\u7b49\u65bc\u7b2c\u4e00\u500b\u8868\u7684\u884c\u6578\u4e58\u4ee5\u7b2c\u4e8c\u500b\u8868\u7684\u884c\u6578\u3002\u901a\u904e\u5177\u9ad4\u7684\u7bc4\u4f8b\uff0c\u6211\u5011\u5c55\u793a\u4e86CROSS JOIN\u7684\u57fa\u672c\u7528\u6cd5\u53ca\u5176\u61c9\u7528\u5834\u666f\u3002\u5c0d\u65bc\u9700\u8981\u9032\u884c\u6578\u64da\u5206\u6790\u548c\u5831\u544a\u751f\u6210\u7684\u7528\u6236\u4f86\u8aaa\uff0c\u638c\u63e1CROSS JOIN\u7684\u4f7f\u7528\u5c07\u5927\u5927\u63d0\u9ad8\u5de5\u4f5c\u6548\u7387\u3002\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u4f86\u652f\u6301\u60a8\u7684MySQL\u6578\u64da\u5eab\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u4f7f\u7528CROSS JOIN\u5728MySQL\u4e2d\u751f\u6210\u7d50\u679c\u96c6\uff0c\u884c\u6578\u70ba\u7b2c\u4e00\u500b\u8868\u8207\u7b2c\u4e8c\u500b\u8868\u884c\u6578\u7684\u4e58\u7a4d\uff0c\u8f15\u9b06\u638c\u63e1\u57fa\u790e\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-76208","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76208","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=76208"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76208\/revisions"}],"predecessor-version":[{"id":76209,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76208\/revisions\/76209"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=76208"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=76208"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=76208"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}