{"id":80130,"date":"2024-10-16T13:56:14","date_gmt":"2024-10-16T05:56:14","guid":{"rendered":"https:\/\/server.hk\/cnblog\/80130\/"},"modified":"2024-10-16T13:56:14","modified_gmt":"2024-10-16T05:56:14","slug":"mysql%e6%8c%87%e4%bb%a4-union%ef%bc%88%e5%90%88%e4%bd%b5%e7%b5%90%e6%9e%9c%e9%9b%86%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/80130\/","title":{"rendered":"MySQL\u6307\u4ee4: UNION\uff08\u5408\u4f75\u7d50\u679c\u96c6\uff09"},"content":{"rendered":"<h1 id=\"mysql%e6%8c%87%e4%bb%a4-union%ef%bc%88%e5%90%88%e4%bd%b5%e7%b5%90%e6%9e%9c%e9%9b%86%ef%bc%89-aldKCPVyUQ\">MySQL\u6307\u4ee4: UNION\uff08\u5408\u4f75\u7d50\u679c\u96c6\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\u5f37\u5927\u7684\u67e5\u8a62\u529f\u80fd\u3002\u5176\u4e2d\uff0cUNION\u6307\u4ee4\u662f\u4e00\u500b\u975e\u5e38\u6709\u7528\u7684\u5de5\u5177\uff0c\u80fd\u5920\u5c07\u591a\u500bSELECT\u67e5\u8a62\u7684\u7d50\u679c\u5408\u4f75\u6210\u4e00\u500b\u7d50\u679c\u96c6\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eUNION\u7684\u7528\u6cd5\u3001\u7279\u6027\u53ca\u5176\u5728\u5be6\u969b\u61c9\u7528\u4e2d\u7684\u793a\u4f8b\u3002<\/p>\n<h2 id=\"union%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-aldKCPVyUQ\">UNION\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>UNION\u6307\u4ee4\u7684\u4e3b\u8981\u529f\u80fd\u662f\u5c07\u5169\u500b\u6216\u591a\u500bSELECT\u67e5\u8a62\u7684\u7d50\u679c\u5408\u4f75\u3002\u4f7f\u7528UNION\u6642\uff0c\u6240\u6709\u7684SELECT\u67e5\u8a62\u5fc5\u9808\u5177\u6709\u76f8\u540c\u7684\u5217\u6578\uff0c\u4e14\u5c0d\u61c9\u7684\u5217\u5fc5\u9808\u5177\u6709\u76f8\u540c\u6216\u76f8\u4f3c\u7684\u6578\u64da\u985e\u578b\u3002\u5408\u4f75\u5f8c\u7684\u7d50\u679c\u96c6\u5c07\u81ea\u52d5\u53bb\u9664\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"union%e7%9a%84%e8%aa%9e%e6%b3%95-aldKCPVyUQ\">UNION\u7684\u8a9e\u6cd5<\/h2>\n<pre><code>SELECT column1, column2, ...\nFROM table1\nWHERE condition1\nUNION\nSELECT column1, column2, ...\nFROM table2\nWHERE condition2;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u8a9e\u6cd5\u4e2d\uff0c\u7b2c\u4e00\u500bSELECT\u67e5\u8a62\u7684\u7d50\u679c\u5c07\u8207\u7b2c\u4e8c\u500bSELECT\u67e5\u8a62\u7684\u7d50\u679c\u5408\u4f75\u3002\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0cUNION\u6307\u4ee4\u6703\u81ea\u52d5\u53bb\u9664\u91cd\u8907\u7684\u884c\u3002\u5982\u679c\u5e0c\u671b\u4fdd\u7559\u6240\u6709\u7684\u884c\uff0c\u5305\u62ec\u91cd\u8907\u7684\u884c\uff0c\u53ef\u4ee5\u4f7f\u7528UNION ALL\u6307\u4ee4\u3002<\/p>\n<h2 id=\"union%e8%88%87union-all%e7%9a%84%e5%8d%80%e5%88%a5-aldKCPVyUQ\">UNION\u8207UNION ALL\u7684\u5340\u5225<\/h2>\n<p>UNION\u548cUNION ALL\u7684\u4e3b\u8981\u5340\u5225\u5728\u65bc\u91cd\u8907\u884c\u7684\u8655\u7406\uff1a<\/p>\n<ul>\n<li><strong>UNION\uff1a<\/strong>\u81ea\u52d5\u53bb\u9664\u91cd\u8907\u7684\u884c\uff0c\u8fd4\u56de\u552f\u4e00\u7684\u7d50\u679c\u96c6\u3002<\/li>\n<li><strong>UNION ALL\uff1a<\/strong>\u4fdd\u7559\u6240\u6709\u7684\u884c\uff0c\u5305\u62ec\u91cd\u8907\u7684\u884c\uff0c\u8fd4\u56de\u5b8c\u6574\u7684\u7d50\u679c\u96c6\u3002<\/li>\n<\/ul>\n<h2 id=\"%e4%bd%bf%e7%94%a8%e7%a4%ba%e4%be%8b-aldKCPVyUQ\">\u4f7f\u7528\u793a\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528UNION\u7684\u793a\u4f8b\uff0c\u5047\u8a2d\u6211\u5011\u6709\u5169\u500b\u8868\u683c\uff1aemployees\u548ccontractors\uff0c\u5169\u8005\u90fd\u6709\u4e00\u500b\u540d\u70baname\u7684\u5217\u3002<\/p>\n<pre><code>SELECT name FROM employees\nUNION\nSELECT name FROM contractors;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u54e1\u5de5\u548c\u627f\u5305\u5546\u7684\u540d\u5b57\uff0c\u4e26\u4e14\u4e0d\u6703\u6709\u91cd\u8907\u7684\u540d\u5b57\u51fa\u73fe\u3002\u5982\u679c\u6211\u5011\u5e0c\u671b\u4fdd\u7559\u6240\u6709\u7684\u540d\u5b57\uff0c\u5305\u62ec\u91cd\u8907\u7684\uff0c\u53ef\u4ee5\u4f7f\u7528UNION ALL\uff1a<\/p>\n<pre><code>SELECT name FROM employees\nUNION ALL\nSELECT name FROM contractors;<\/code><\/pre>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-aldKCPVyUQ\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u5728\u4f7f\u7528UNION\u6642\uff0c\u6709\u5e7e\u500b\u6ce8\u610f\u4e8b\u9805\u9700\u8981\u8003\u616e\uff1a<\/p>\n<ul>\n<li>\u6240\u6709\u7684SELECT\u67e5\u8a62\u5fc5\u9808\u8fd4\u56de\u76f8\u540c\u6578\u91cf\u7684\u5217\u3002<\/li>\n<li>\u5c0d\u61c9\u7684\u5217\u5fc5\u9808\u5177\u6709\u76f8\u540c\u6216\u76f8\u4f3c\u7684\u6578\u64da\u985e\u578b\u3002<\/li>\n<li>UNION\u7684\u7d50\u679c\u96c6\u5c07\u6839\u64da\u7b2c\u4e00\u500bSELECT\u67e5\u8a62\u7684\u5217\u9806\u5e8f\u9032\u884c\u6392\u5e8f\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%af%a6%e9%9a%9b%e6%87%89%e7%94%a8%e5%a0%b4%e6%99%af-aldKCPVyUQ\">\u5be6\u969b\u61c9\u7528\u5834\u666f<\/h2>\n<p>UNION\u6307\u4ee4\u5728\u8a31\u591a\u5be6\u969b\u61c9\u7528\u4e2d\u90fd\u975e\u5e38\u6709\u7528\u3002\u4f8b\u5982\uff0c\u5728\u5831\u544a\u4e2d\u9700\u8981\u5f9e\u4e0d\u540c\u7684\u8868\u683c\u4e2d\u63d0\u53d6\u6578\u64da\uff0c\u6216\u8005\u5728\u6578\u64da\u6574\u5408\u904e\u7a0b\u4e2d\u9700\u8981\u5408\u4f75\u4f86\u81ea\u4e0d\u540c\u4f86\u6e90\u7684\u6578\u64da\u6642\uff0cUNION\u90fd\u80fd\u63d0\u4f9b\u4fbf\u5229\u3002\u6b64\u5916\uff0cUNION\u4e5f\u53ef\u4ee5\u7528\u65bc\u6578\u64da\u5206\u6790\uff0c\u5e6b\u52a9\u7528\u6236\u5f9e\u591a\u500b\u8cc7\u6599\u4f86\u6e90\u4e2d\u7372\u53d6\u7d9c\u5408\u4fe1\u606f\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-aldKCPVyUQ\">\u7e3d\u7d50<\/h2>\n<p>UNION\u6307\u4ee4\u662fMySQL\u4e2d\u4e00\u500b\u5f37\u5927\u7684\u529f\u80fd\uff0c\u80fd\u5920\u6709\u6548\u5730\u5408\u4f75\u591a\u500b\u67e5\u8a62\u7684\u7d50\u679c\u96c6\u3002\u7121\u8ad6\u662f\u5728\u6578\u64da\u6574\u5408\u3001\u5831\u544a\u751f\u6210\u9084\u662f\u6578\u64da\u5206\u6790\u4e2d\uff0cUNION\u90fd\u80fd\u63d0\u4f9b\u91cd\u8981\u7684\u652f\u6301\u3002\u4e86\u89e3UNION\u53ca\u5176\u7528\u6cd5\uff0c\u5c07\u6709\u52a9\u65bc\u63d0\u5347\u8cc7\u6599\u5eab\u67e5\u8a62\u7684\u6548\u7387\u548c\u9748\u6d3b\u6027\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc\u8cc7\u6599\u5eab\u7ba1\u7406\u6216\u5176\u4ed6\u76f8\u95dc\u6280\u8853\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\uff0c\u7279\u5225\u662f\u6211\u5011\u63d0\u4f9b\u7684<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u89e3\u6c7a\u65b9\u6848\uff0c\u52a9\u60a8\u5728\u6578\u64da\u7ba1\u7406\u4e0a\u66f4\u4e0a\u4e00\u5c64\u6a13\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3MySQL\u4e2d\u7684UNION\u6307\u4ee4\uff0c\u5b78\u7fd2\u5982\u4f55\u5408\u4f75\u591a\u500b\u67e5\u8a62\u7d50\u679c\u96c6\uff0c\u63d0\u5347\u6578\u64da\u8655\u7406\u6548\u7387\u8207\u9748\u6d3b\u6027\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-80130","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/80130","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=80130"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/80130\/revisions"}],"predecessor-version":[{"id":80131,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/80130\/revisions\/80131"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=80130"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=80130"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=80130"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}