{"id":1776,"date":"2025-02-18T00:28:24","date_gmt":"2025-02-17T16:28:24","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=1776"},"modified":"2025-02-18T00:28:24","modified_gmt":"2025-02-17T16:28:24","slug":"mysql-union-%e6%93%8d%e4%bd%9c%ef%bc%88%e9%99%84%e5%b8%a6%e5%ae%9e%e4%be%8b%ef%bc%89","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/02\/18\/mysql-union-%e6%93%8d%e4%bd%9c%ef%bc%88%e9%99%84%e5%b8%a6%e5%ae%9e%e4%be%8b%ef%bc%89\/","title":{"rendered":"MySQL UNION \u64cd\u4f5c\uff08\u9644\u5e26\u5b9e\u4f8b\uff09"},"content":{"rendered":"\n

\u5728 MySQL \u4e2d\uff0cUNION<\/code> \u64cd\u4f5c\u7b26\u7528\u4e8e\u5c06\u591a\u4e2a SELECT<\/code> \u67e5\u8be2\u7684\u7ed3\u679c\u5408\u5e76\u6210\u4e00\u4e2a\u7ed3\u679c\u96c6\u3002\u5b83\u53ef\u4ee5\u5c06\u6765\u81ea\u591a\u4e2a\u8868\u6216\u591a\u4e2a\u67e5\u8be2\u7684\u7ed3\u679c\u6309\u884c\u62fc\u63a5\u8d77\u6765\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cUNION<\/code> \u4f1a\u53bb\u9664\u91cd\u590d\u7684\u8bb0\u5f55\uff0c\u5982\u679c\u4f60\u60f3\u4fdd\u7559\u91cd\u590d\u7684\u8bb0\u5f55\uff0c\u53ef\u4ee5\u4f7f\u7528 UNION ALL<\/code>\u3002<\/p>\n\n\n\n

1. UNION<\/code> \u64cd\u4f5c\u7b26\u7684\u57fa\u672c\u8bed\u6cd5<\/strong><\/h3>\n\n\n\n
SELECT column1, column2, ...\nFROM table1\nWHERE condition\nUNION\nSELECT column1, column2, ...\nFROM table2\nWHERE condition;<\/code><\/pre>\n\n\n\n
    \n
  • SELECT column1, column2, ...<\/code>\uff1a\u4f60\u8981\u4ece\u8868\u4e2d\u9009\u53d6\u7684\u5217\u3002<\/li>\n\n\n\n
  • FROM table1, table2<\/code>\uff1a\u4f60\u8981\u67e5\u8be2\u7684\u8868\u3002<\/li>\n\n\n\n
  • WHERE condition<\/code>\uff1a\u67e5\u8be2\u6761\u4ef6\uff0c\u9650\u5236\u4f60\u8981\u8fd4\u56de\u7684\u6570\u636e\u3002<\/li>\n<\/ul>\n\n\n\n
    2. UNION<\/code> \u7684\u4f7f\u7528\u89c4\u5219<\/strong><\/h3>\n\n\n\n
      \n
    • \u6240\u6709\u7684 SELECT<\/code> \u67e5\u8be2\u5fc5\u987b\u8fd4\u56de\u76f8\u540c\u6570\u91cf\u7684\u5217\uff0c\u5e76\u4e14\u6bcf\u5217\u7684\u987a\u5e8f\u548c\u6570\u636e\u7c7b\u578b\u5fc5\u987b\u517c\u5bb9\u3002<\/li>\n\n\n\n
    • \u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cUNION<\/code> \u4f1a\u5220\u9664\u91cd\u590d\u7684\u8bb0\u5f55\u3002\u5982\u679c\u4f60\u5e0c\u671b\u4fdd\u7559\u91cd\u590d\u8bb0\u5f55\uff0c\u5e94\u8be5\u4f7f\u7528 UNION ALL<\/code>\u3002<\/li>\n<\/ul>\n\n\n\n
      3. \u5b9e\u4f8b\uff1aUNION<\/code> \u64cd\u4f5c\u7b26\u7684\u4f7f\u7528<\/strong><\/h3>\n\n\n\n
      \u5047\u8bbe\u4f60\u6709\u4e24\u4e2a\u8868\uff1aemployees<\/code> \u548c managers<\/code>\uff0c\u5b83\u4eec\u90fd\u6709\u76f8\u540c\u7684\u5b57\u6bb5\u7ed3\u6784\uff1aid<\/code>, name<\/code>, \u548c position<\/code>\u3002<\/p>\n\n\n\n
      \u793a\u4f8b 1\uff1a\u4f7f\u7528 UNION<\/code> \u5408\u5e76\u6765\u81ea\u4e0d\u540c\u8868\u7684\u6570\u636e<\/strong><\/h4>\n\n\n\n
      SELECT id, name, position FROM employees\nUNION\nSELECT id, name, position FROM managers;<\/code><\/pre>\n\n\n\n
        \n
      • \u8fd9\u4e2a\u67e5\u8be2\u5c06\u4ece employees<\/code> \u8868\u548c managers<\/code> \u8868\u4e2d\u83b7\u53d6 id<\/code>, name<\/code>, \u548c position<\/code> \u5b57\u6bb5\u7684\u8bb0\u5f55\uff0c\u5e76\u5c06\u5b83\u4eec\u5408\u5e76\u5230\u4e00\u4e2a\u7ed3\u679c\u96c6\u4e2d\u3002\u7ed3\u679c\u5c06\u53bb\u9664\u91cd\u590d\u7684\u8bb0\u5f55\u3002<\/li>\n<\/ul>\n\n\n\n
        \u793a\u4f8b 2\uff1a\u4f7f\u7528 UNION ALL<\/code> \u4fdd\u7559\u91cd\u590d\u7684\u8bb0\u5f55<\/strong><\/h4>\n\n\n\n
        SELECT id, name, position FROM employees\nUNION ALL\nSELECT id, name, position FROM managers;<\/code><\/pre>\n\n\n\n
          \n
        • \u8fd9\u4e2a\u67e5\u8be2\u4e0e\u4e0a\u9762\u7684\u67e5\u8be2\u7c7b\u4f3c\uff0c\u4f46\u4f1a\u4fdd\u7559\u91cd\u590d\u7684\u8bb0\u5f55\u3002\u5982\u679c employees<\/code> \u8868\u548c managers<\/code> \u8868\u4e2d\u6709\u76f8\u540c\u7684 id<\/code>, name<\/code>, \u548c position<\/code> \u7ec4\u5408\uff0cUNION ALL<\/code> \u4f1a\u8fd4\u56de\u5b83\u4eec\u3002<\/li>\n<\/ul>\n\n\n\n
          4. UNION<\/code> \u4e0e\u6392\u5e8f<\/strong><\/h3>\n\n\n\n
          \u4f60\u53ef\u4ee5\u5728 UNION<\/code> \u67e5\u8be2\u7ed3\u679c\u7684\u6700\u540e\u4f7f\u7528 ORDER BY<\/code> \u6765\u6392\u5e8f\u6574\u4e2a\u7ed3\u679c\u96c6\u3002\u6ce8\u610f\uff0cORDER BY<\/code> \u53ea\u80fd\u51fa\u73b0\u5728 UNION<\/code> \u67e5\u8be2\u7684\u6700\u540e\u4e00\u4e2a\u90e8\u5206\uff0c\u800c\u4e0d\u80fd\u51fa\u73b0\u5728\u5355\u4e2a SELECT<\/code> \u67e5\u8be2\u4e2d\u3002<\/p>\n\n\n\n
          \u793a\u4f8b 3\uff1a\u4f7f\u7528 ORDER BY<\/code> \u5bf9\u5408\u5e76\u7ed3\u679c\u8fdb\u884c\u6392\u5e8f<\/strong><\/h4>\n\n\n\n
          SELECT id, name, position FROM employees\nUNION\nSELECT id, name, position FROM managers\nORDER BY name ASC;<\/code><\/pre>\n\n\n\n
            \n
          • \u8fd9\u4e2a\u67e5\u8be2\u5c06\u6839\u636e name<\/code> \u5b57\u6bb5\u6309\u5347\u5e8f\u5bf9\u7ed3\u679c\u8fdb\u884c\u6392\u5e8f\u3002<\/li>\n<\/ul>\n\n\n\n
            5. UNION<\/code> \u4e0e LIMIT<\/code><\/strong><\/h3>\n\n\n\n
            \u5982\u679c\u4f60\u5e0c\u671b\u9650\u5236\u8fd4\u56de\u7684\u8bb0\u5f55\u6570\uff0c\u53ef\u4ee5\u4f7f\u7528 LIMIT<\/code> \u5b50\u53e5\uff0c\u4f46\u8981\u6ce8\u610f LIMIT<\/code> \u53ea\u80fd\u9650\u5236\u6574\u4e2a UNION<\/code> \u67e5\u8be2\u7ed3\u679c\u7684\u8bb0\u5f55\u6570\uff0c\u800c\u4e0d\u80fd\u5355\u72ec\u9650\u5236\u6bcf\u4e2a SELECT<\/code> \u5b50\u67e5\u8be2\u7684\u7ed3\u679c\u3002<\/p>\n\n\n\n
            \u793a\u4f8b 4\uff1a\u5bf9 UNION<\/code> \u67e5\u8be2\u7ed3\u679c\u4f7f\u7528 LIMIT<\/code><\/strong><\/h4>\n\n\n\n
            SELECT id, name, position FROM employees\nUNION\nSELECT id, name, position FROM managers\nLIMIT 10;<\/code><\/pre>\n\n\n\n
              \n
            • \u8fd9\u4e2a\u67e5\u8be2\u5c06\u5408\u5e76\u6765\u81ea employees<\/code> \u548c managers<\/code> \u8868\u7684\u8bb0\u5f55\uff0c\u5e76\u53ea\u8fd4\u56de\u524d 10 \u6761\u8bb0\u5f55\u3002<\/li>\n<\/ul>\n\n\n\n
              6. UNION<\/code> \u4e0e JOIN<\/code> \u7684\u6bd4\u8f83<\/strong><\/h3>\n\n\n\n
              UNION<\/code> \u548c JOIN<\/code> \u90fd\u53ef\u4ee5\u7528\u4e8e\u5408\u5e76\u591a\u4e2a\u8868\u7684\u6570\u636e\uff0c\u4f46\u5b83\u4eec\u7684\u5de5\u4f5c\u65b9\u5f0f\u4e0d\u540c\uff1a<\/p>\n\n\n\n
                \n
              • UNION<\/code> \u5408\u5e76\u591a\u4e2a\u67e5\u8be2\u7684\u7ed3\u679c\u96c6\uff0c\u8fd4\u56de\u7684\u884c\u662f\u4e0d\u540c\u67e5\u8be2\u7684\u62fc\u63a5\u3002<\/li>\n\n\n\n
              • JOIN<\/code> \u901a\u8fc7\u57fa\u4e8e\u5171\u540c\u5b57\u6bb5\u8fde\u63a5\u591a\u4e2a\u8868\uff0c\u8fd4\u56de\u7684\u662f\u8de8\u8868\u7684\u8054\u5408\u6570\u636e\u3002<\/li>\n<\/ul>\n\n\n\n
                \u793a\u4f8b 5\uff1aJOIN<\/code> \u4e0e UNION<\/code> \u7684\u533a\u522b<\/strong><\/h4>\n\n\n\n
                \u5047\u8bbe\u6709\u4e24\u4e2a\u8868\uff1aemployees<\/code> \u548c departments<\/code>\uff0c\u5e76\u4e14\u4f60\u60f3\u8981\u83b7\u53d6\u5458\u5de5\u53ca\u5176\u90e8\u95e8\u7684\u4fe1\u606f\u3002<\/p>\n\n\n\n
                  \n
                • \u4f7f\u7528 JOIN<\/code>\uff1a<\/li>\n<\/ul>\n\n\n\n
                  SELECT employees.name, employees.position, departments.department_name\nFROM employees\nJOIN departments ON employees.department_id = departments.id;<\/code><\/pre>\n\n\n\n
                    \n
                  • \u4f7f\u7528 UNION<\/code>\uff08\u5047\u8bbe\u4f60\u6709\u4e0d\u540c\u7684\u67e5\u8be2\uff0c\u60f3\u5408\u5e76\u5b83\u4eec\uff09\uff1a<\/li>\n<\/ul>\n\n\n\n
                    SELECT name, position FROM employees\nUNION\nSELECT name, position FROM managers;<\/code><\/pre>\n\n\n\n
                      \n
                    • JOIN<\/code> \u7528\u4e8e\u6839\u636e\u67d0\u4e2a\u516c\u5171\u5b57\u6bb5\uff08\u5982 department_id<\/code>\uff09\u5c06\u8868\u8fde\u63a5\u5728\u4e00\u8d77\uff0c\u8fd4\u56de\u8de8\u8868\u7684\u6570\u636e\u3002<\/li>\n\n\n\n
                    • UNION<\/code> \u7528\u4e8e\u5408\u5e76\u6765\u81ea\u4e0d\u540c\u67e5\u8be2\u7684\u7ed3\u679c\u96c6\uff0c\u884c\u4e4b\u95f4\u6ca1\u6709\u76f4\u63a5\u5173\u7cfb\u3002<\/li>\n<\/ul>\n\n\n\n
                      7. \u6ce8\u610f\u4e8b\u9879<\/strong><\/h3>\n\n\n\n
                        \n
                      • \u5217\u7684\u6570\u91cf\u4e0e\u6570\u636e\u7c7b\u578b<\/strong>\uff1aUNION<\/code> \u7684\u6bcf\u4e2a\u67e5\u8be2\u8fd4\u56de\u7684\u5217\u6570\u548c\u6570\u636e\u7c7b\u578b\u5fc5\u987b\u76f8\u540c\u3002\u5426\u5219\uff0cMySQL \u4f1a\u62a5\u9519\u3002<\/li>\n\n\n\n
                      • \u9ed8\u8ba4\u53bb\u91cd<\/strong>\uff1aUNION<\/code> \u4f1a\u53bb\u9664\u91cd\u590d\u7684\u8bb0\u5f55\u3002\u5982\u679c\u4f60\u5e0c\u671b\u4fdd\u7559\u91cd\u590d\u8bb0\u5f55\uff0c\u53ef\u4ee5\u4f7f\u7528 UNION ALL<\/code>\u3002<\/li>\n\n\n\n
                      • \u6392\u5e8f\u4e0e\u5206\u9875<\/strong>\uff1aORDER BY<\/code> \u548c LIMIT<\/code> \u5e94\u653e\u5728 UNION<\/code> \u67e5\u8be2\u7684\u6700\u540e\u90e8\u5206\u3002ORDER BY<\/code> \u4f1a\u5bf9\u6574\u4e2a\u7ed3\u679c\u96c6\u8fdb\u884c\u6392\u5e8f\uff0c\u800c\u4e0d\u662f\u5355\u72ec\u7684\u67e5\u8be2\u3002<\/li>\n<\/ul>\n\n\n\n
                        \n\n\n\n
                        \u603b\u7ed3<\/h3>\n\n\n\n
                          \n
                        • UNION<\/code> \u7528\u4e8e\u5c06\u591a\u4e2a SELECT<\/code> \u67e5\u8be2\u7684\u7ed3\u679c\u5408\u5e76\u6210\u4e00\u4e2a\u7ed3\u679c\u96c6\uff0c\u9ed8\u8ba4\u53bb\u9664\u91cd\u590d\u8bb0\u5f55\u3002<\/li>\n\n\n\n
                        • UNION ALL<\/code> \u7528\u4e8e\u5c06\u591a\u4e2a\u67e5\u8be2\u7684\u7ed3\u679c\u5408\u5e76\u5e76\u4fdd\u7559\u91cd\u590d\u8bb0\u5f55\u3002<\/li>\n\n\n\n
                        • UNION<\/code> \u67e5\u8be2\u53ef\u4ee5\u4f7f\u7528 ORDER BY<\/code> \u6765\u5bf9\u5408\u5e76\u7684\u7ed3\u679c\u8fdb\u884c\u6392\u5e8f\uff0c\u5e76\u4f7f\u7528 LIMIT<\/code> \u6765\u9650\u5236\u8fd4\u56de\u7684\u8bb0\u5f55\u6570\u3002<\/li>\n\n\n\n
                        • UNION<\/code> \u548c JOIN<\/code> \u7684\u4f7f\u7528\u573a\u666f\u4e0d\u540c\uff0cUNION<\/code> \u7528\u4e8e\u5408\u5e76\u67e5\u8be2\u7ed3\u679c\uff0cJOIN<\/code> \u7528\u4e8e\u8de8\u8868\u8fde\u63a5\u6570\u636e\u3002<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"
                          \u5728 MySQL \u4e2d\uff0cUNION \u64cd\u4f5c\u7b26\u7528\u4e8e\u5c06\u591a\u4e2a SELECT \u67e5\u8be2\u7684\u7ed3\u679c\u5408\u5e76\u6210\u4e00\u4e2a\u7ed3\u679c\u96c6\u3002\u5b83\u53ef\u4ee5\u5c06\u6765\u81ea\u591a\u4e2a\u8868 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[],"class_list":["post-1776","post","type-post","status-publish","format-standard","hentry","category-mysql"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/1776","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=1776"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/1776\/revisions"}],"predecessor-version":[{"id":1777,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/1776\/revisions\/1777"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=1776"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=1776"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=1776"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}