{"id":75736,"date":"2024-10-16T00:47:17","date_gmt":"2024-10-15T16:47:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/75736\/"},"modified":"2024-10-16T00:47:17","modified_gmt":"2024-10-15T16:47:17","slug":"mysql-union%e8%aa%9e%e6%b3%95%e4%bb%a3%e7%a2%bc%e6%bc%94%e7%a4%ba","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/75736\/","title":{"rendered":"MySQL UNION\u8a9e\u6cd5\u4ee3\u78bc\u6f14\u793a"},"content":{"rendered":"<h1 id=\"mysql-union%e8%aa%9e%e6%b3%95%e4%bb%a3%e7%a2%bc%e6%bc%94%e7%a4%ba-euNbveDhBF\">MySQL UNION\u8a9e\u6cd5\u4ee3\u78bc\u6f14\u793a<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u95dc\u806f\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u3002\u5b83\u63d0\u4f9b\u4e86\u591a\u7a2e\u67e5\u8a62\u529f\u80fd\uff0c\u5176\u4e2d\u4e4b\u4e00\u5c31\u662fUNION\u8a9e\u6cd5\u3002UNION\u8a9e\u6cd5\u5141\u8a31\u7528\u6236\u5c07\u5169\u500b\u6216\u591a\u500bSELECT\u67e5\u8a62\u7684\u7d50\u679c\u5408\u4f75\u70ba\u4e00\u500b\u7d50\u679c\u96c6\u3002\u9019\u5c0d\u65bc\u9700\u8981\u5f9e\u4e0d\u540c\u8868\u4e2d\u63d0\u53d6\u6578\u64da\u7684\u60c5\u6cc1\u7279\u5225\u6709\u7528\u3002<\/p>\n<h2 id=\"union%e7%9a%84%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-euNbveDhBF\">UNION\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p>UNION\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT column1, column2, ...\nFROM table1\nWHERE condition\nUNION\nSELECT column1, column2, ...\nFROM table2\nWHERE condition;<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0c\u5169\u500bSELECT\u67e5\u8a62\u7684\u5217\u6578\u548c\u6578\u64da\u985e\u578b\u5fc5\u9808\u76f8\u540c\u3002UNION\u6703\u81ea\u52d5\u53bb\u9664\u91cd\u8907\u7684\u8a18\u9304\u3002\u5982\u679c\u9700\u8981\u4fdd\u7559\u91cd\u8907\u7684\u8a18\u9304\uff0c\u53ef\u4ee5\u4f7f\u7528UNION ALL\u3002<\/p>\n<h2 id=\"union%e7%9a%84%e4%bd%bf%e7%94%a8%e7%a4%ba%e4%be%8b-euNbveDhBF\">UNION\u7684\u4f7f\u7528\u793a\u4f8b<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u5169\u500b\u8868\uff1a<code>employees<\/code>\u548c<code>contractors<\/code>\uff0c\u5b83\u5011\u90fd\u5305\u542b\u54e1\u5de5\u7684\u59d3\u540d\u548c\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u3002\u6211\u5011\u5e0c\u671b\u5f9e\u9019\u5169\u500b\u8868\u4e2d\u7372\u53d6\u6240\u6709\u7684\u59d3\u540d\u548c\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u3002<\/p>\n<pre><code>SELECT name, email\nFROM employees\nUNION\nSELECT name, email\nFROM contractors;<\/code><\/pre>\n<p>\u9019\u6bb5\u4ee3\u78bc\u5c07\u8fd4\u56de\u6240\u6709\u54e1\u5de5\u548c\u627f\u5305\u5546\u7684\u59d3\u540d\u548c\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\uff0c\u4e26\u4e14\u4e0d\u6703\u6709\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8union-all-euNbveDhBF\">\u4f7f\u7528UNION ALL<\/h2>\n<p>\u5982\u679c\u6211\u5011\u5e0c\u671b\u4fdd\u7559\u91cd\u8907\u7684\u8a18\u9304\uff0c\u53ef\u4ee5\u4f7f\u7528UNION ALL\u3002\u4ee5\u4e0b\u662f\u4f7f\u7528UNION ALL\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT name, email\nFROM employees\nUNION ALL\nSELECT name, email\nFROM contractors;<\/code><\/pre>\n<p>\u9019\u6bb5\u4ee3\u78bc\u5c07\u8fd4\u56de\u6240\u6709\u54e1\u5de5\u548c\u627f\u5305\u5546\u7684\u59d3\u540d\u548c\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\uff0c\u5305\u62ec\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-euNbveDhBF\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<ul>\n<li>\u6240\u6709SELECT\u67e5\u8a62\u7684\u5217\u6578\u5fc5\u9808\u76f8\u540c\u3002<\/li>\n<li>\u5c0d\u61c9\u7684\u5217\u5fc5\u9808\u5177\u6709\u76f8\u540c\u6216\u517c\u5bb9\u7684\u6578\u64da\u985e\u578b\u3002<\/li>\n<li>UNION\u6703\u81ea\u52d5\u53bb\u9664\u91cd\u8907\u7684\u8a18\u9304\uff0c\u800cUNION ALL\u5247\u4e0d\u6703\u3002<\/li>\n<li>UNION\u7684\u6027\u80fd\u901a\u5e38\u6bd4UNION ALL\u7a0d\u6162\uff0c\u56e0\u70ba\u5b83\u9700\u8981\u9032\u884c\u91cd\u8907\u8a18\u9304\u7684\u6aa2\u67e5\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-euNbveDhBF\">\u5be6\u969b\u61c9\u7528\u5834\u666f<\/h2>\n<p>UNION\u8a9e\u6cd5\u5728\u8a31\u591a\u5be6\u969b\u61c9\u7528\u4e2d\u90fd\u975e\u5e38\u6709\u7528\u3002\u4f8b\u5982\uff0c\u7576\u9700\u8981\u5f9e\u591a\u500b\u4f86\u6e90\u7372\u53d6\u5831\u544a\u6578\u64da\u6642\uff0cUNION\u53ef\u4ee5\u5e6b\u52a9\u6574\u5408\u9019\u4e9b\u6578\u64da\u3002\u5047\u8a2d\u4e00\u5bb6\u516c\u53f8\u6709\u591a\u500b\u90e8\u9580\uff0c\u6bcf\u500b\u90e8\u9580\u90fd\u6709\u81ea\u5df1\u7684\u6578\u64da\u8868\uff0c\u4f7f\u7528UNION\u53ef\u4ee5\u8f15\u9b06\u5730\u751f\u6210\u4e00\u500b\u7d9c\u5408\u5831\u544a\u3002<\/p>\n<h2 id=\"%e7%b5%90%e8%ab%96-euNbveDhBF\">\u7d50\u8ad6<\/h2>\n<p>MySQL\u7684UNION\u8a9e\u6cd5\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u80fd\u5920\u5e6b\u52a9\u7528\u6236\u5f9e\u591a\u500b\u8868\u4e2d\u63d0\u53d6\u548c\u5408\u4f75\u6578\u64da\u3002\u901a\u904e\u6b63\u78ba\u4f7f\u7528UNION\u548cUNION ALL\uff0c\u7528\u6236\u53ef\u4ee5\u9748\u6d3b\u5730\u8655\u7406\u6578\u64da\uff0c\u6eff\u8db3\u5404\u7a2e\u67e5\u8a62\u9700\u6c42\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u7ba1\u7406\u7684\u4f01\u696d\u4f86\u8aaa\uff0c\u638c\u63e1\u9019\u4e9b\u8a9e\u6cd5\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u53ef\u9760\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK\u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u60a8\u7684\u9700\u6c42\u3002\u7121\u8ad6\u662f\u6578\u64da\u5eab\u7ba1\u7406\u9084\u662f\u7db2\u7ad9\u6258\u7ba1\uff0c\u6211\u5011\u7684\u670d\u52d9\u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22MySQL UNION\u8a9e\u6cd5\u7684\u4ee3\u78bc\u793a\u7bc4\uff0c\u5b78\u7fd2\u5982\u4f55\u5408\u4f75\u591a\u500b\u67e5\u8a62\u7d50\u679c\uff0c\u63d0\u5347\u6578\u64da\u8655\u7406\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-75736","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75736","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=75736"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75736\/revisions"}],"predecessor-version":[{"id":75737,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75736\/revisions\/75737"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=75736"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=75736"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=75736"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}