{"id":6662,"date":"2024-11-14T13:57:38","date_gmt":"2024-11-14T05:57:38","guid":{"rendered":"https:\/\/fwq.ai\/blog\/6662\/"},"modified":"2024-11-14T13:57:38","modified_gmt":"2024-11-14T05:57:38","slug":"group-by%e7%94%a8%e6%b3%95","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/6662\/","title":{"rendered":"group by\u7528\u6cd5"},"content":{"rendered":"

\n group by \u662f\u4e00\u79cd sql \u805a\u5408\u51fd\u6570\uff0c\u53ef\u5bf9\u8868\u6570\u636e\u6309\u5217\u5206\u7ec4\uff0c\u5e76\u5bf9\u6bcf\u4e2a\u7ec4\u8fdb\u884c\u805a\u5408\u8ba1\u7b97\u3002\u8bed\u6cd5\uff1a1. \u6307\u5b9a\u5206\u7ec4\u5217\uff1agroup by \u5b50\u53e5\u4e2d\u6307\u5b9a\u8981\u5206\u7ec4\u7684\u5217\u30022. \u6267\u884c\u805a\u5408\u8ba1\u7b97\uff1a\u4f7f\u7528\u805a\u5408\u51fd\u6570\u5bf9\u5206\u7ec4\u5217\u8ba1\u7b97\u30023. \u6839\u636e\u5206\u7ec4\u83b7\u53d6\u7ed3\u679c\uff1a\u67e5\u8be2\u8fd4\u56de\u805a\u5408\u7ed3\u679c\uff0c\u6bcf\u4e00\u884c\u4e3a\u4e00\u4e2a\u7ec4\u3002\n<\/p><\/blockquote>\n

\"group<\/p>\n

GROUP BY \u7528\u6cd5<\/strong><\/p>\n

\u5b9a\u4e49<\/strong><\/p>\n

GROUP BY \u662f\u4e00\u79cd SQL \uff0c\u7528\u4e8e\u6839\u636e\u5217\u5bf9\u8868\u4e2d\u6570\u636e\u8fdb\u884c\u5206\u7ec4\uff0c\u5e76\u5bf9\u6bcf\u4e2a\u7ec4\u7684\u7279\u5b9a\u5217\u8fdb\u884c\u805a\u5408\u8ba1\u7b97\u3002<\/p>\n

\u8bed\u6cd5<\/strong><\/p>\n

SELECT \u805a\u5408\u51fd\u6570(\u5217\u540d)\nFROM \u8868\u540d\nGROUP BY \u5206\u7ec4\u5217\u540d;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u53c2\u6570<\/strong><\/p>\n
    \n
  •  \u805a\u5408\u51fd\u6570\uff1a<\/strong>\u7528\u4e8e\u6267\u884c\u805a\u5408\u8ba1\u7b97\u7684\u51fd\u6570\uff0c\u5982 SUM\u3001COUNT\u3001AVG \u7b49\u3002<\/li>\n
  •  \u5217\u540d\uff1a<\/strong>\u7528\u4e8e\u8fdb\u884c\u805a\u5408\u8ba1\u7b97\u7684\u5217\u3002<\/li>\n
  •  \u5206\u7ec4\u5217\u540d\uff1a<\/strong>\u7528\u4e8e\u5206\u7ec4\u5408\u5e76\u7684\u5217\u3002<\/li>\n<\/ul>\n
    \u7528\u6cd5<\/strong><\/p>\n
    GROUP BY \u7528\u6cd5\u5982\u4e0b\uff1a<\/p>\n
      \n
    1.  \u6307\u5b9a\u5206\u7ec4\u5217\uff1a<\/strong>\u5728 GROUP BY \u5b50\u53e5\u4e2d\u6307\u5b9a\u8981\u7528\u4e8e\u5206\u7ec4\u7684\u5217\u3002<\/li>\n
    2.  \u6267\u884c\u805a\u5408\u8ba1\u7b97\uff1a<\/strong>\u4f7f\u7528\u805a\u5408\u51fd\u6570\u5bf9\u6bcf\u4e2a\u7ec4\u7684\u5217\u8fdb\u884c\u8ba1\u7b97\u3002<\/li>\n
    3.  \u6839\u636e\u7ec4\u83b7\u53d6\u7ed3\u679c\uff1a<\/strong>\u5206\u7ec4\u5b8c\u6210\u540e\uff0cSQL \u67e5\u8be2\u5c06\u8fd4\u56de\u805a\u5408\u8ba1\u7b97\u7684\u7ed3\u679c\uff0c\u5176\u4e2d\u6bcf\u4e00\u884c\u4ee3\u8868\u4e00\u4e2a\u7ec4\u3002<\/li>\n<\/ol>\n
      \u793a\u4f8b<\/strong><\/p>\n
      \u4ee5\u4e0b\u793a\u4f8b\u6f14\u793a\u5982\u4f55\u4f7f\u7528 GROUP BY \u6765\u8ba1\u7b97\u4e0d\u540c\u90e8\u95e8\u7684\u5458\u5de5\u4eba\u6570\uff1a<\/p>\n
      SELECT \u90e8\u95e8, COUNT(*) AS \u4eba\u6570\nFROM \u5458\u5de5\u8868\nGROUP BY \u90e8\u95e8;<\/pre>\n
       \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
      \u67e5\u8be2\u7ed3\u679c\u5982\u4e0b\uff1a<\/p>\n\n\n\n\n\n\n\n
      \u90e8\u95e8<\/th>\n\u4eba\u6570<\/th>\n<\/tr>\n<\/thead>\n
      \u9500\u552e<\/td>\n10<\/td>\n<\/tr>\n
      \u5e02\u573a<\/td>\n5<\/td>\n<\/tr>\n
      \u7814\u53d1<\/td>\n15<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
      \u4f18\u70b9<\/strong><\/p>\n
      GROUP BY \u7684\u4e3b\u8981\u4f18\u70b9\u5305\u62ec\uff1a<\/p>\n
        \n
      •  \u6570\u636e\u5206\u7ec4\uff1a<\/strong>\u5b83\u5141\u8bb8\u5c06\u6570\u636e\u7ec4\u7ec7\u5230\u4e0d\u540c\u7684\u7ec4\u4e2d\u3002<\/li>\n
      •  \u6570\u636e\u6458\u8981\uff1a<\/strong>\u901a\u8fc7\u805a\u5408\u8ba1\u7b97\uff0c\u5b83\u63d0\u4f9b\u4e86\u6570\u636e\u7684\u6458\u8981\u89c6\u56fe\u3002<\/li>\n
      •  \u6027\u80fd\u4f18\u5316\uff1a<\/strong>\u5b83\u53ef\u4ee5\u6539\u5584\u5bf9\u5927\u578b\u6570\u636e\u96c6\u8fdb\u884c\u67e5\u8be2\u7684\u6027\u80fd\uff0c\u56e0\u4e3a\u5b83\u51cf\u5c11\u4e86\u67e5\u8be2\u8fd4\u56de\u7684\u884c\u6570\u3002<\/li>\n<\/ul>\n
        \u4ee5\u4e0a\u5c31\u662fgroup by\u7528\u6cd5\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u7f51\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
        group by \u662f\u4e00\u79cd sql \u805a\u5408\u51fd\u6570\uff0c\u53ef\u5bf9\u8868\u6570\u636e\u6309\u5217\u5206\u7ec4\uff0c\u5e76\u5bf9\u6bcf\u4e2a\u7ec4\u8fdb\u884c\u805a\u5408\u8ba1\u7b97\u3002\u8bed\u6cd5\uff1a1. \u6307\u5b9a\u5206\u7ec4\u5217\uff1agroup by \u5b50\u53e5\u4e2d\u6307\u5b9a\u8981\u5206\u7ec4\u7684\u5217\u30022. \u6267\u884c\u805a\u5408\u8ba1\u7b97\uff1a\u4f7f\u7528\u805a\u5408\u51fd\u6570\u5bf9\u5206\u7ec4\u5217\u8ba1\u7b97\u30023. \u6839\u636e\u5206\u7ec4\u83b7\u53d6\u7ed3\u679c\uff1a\u67e5\u8be2\u8fd4\u56de\u805a\u5408\u7ed3\u679c\uff0c\u6bcf\u4e00\u884c\u4e3a\u4e00\u4e2a\u7ec4\u3002 GROUP BY \u7528\u6cd5 \u5b9a\u4e49 GROUP BY \u662f\u4e00\u79cd SQL \uff0c\u7528\u4e8e\u6839\u636e\u5217\u5bf9\u8868\u4e2d\u6570\u636e\u8fdb\u884c\u5206\u7ec4\uff0c\u5e76\u5bf9\u6bcf\u4e2a\u7ec4\u7684\u7279\u5b9a\u5217\u8fdb\u884c\u805a\u5408\u8ba1\u7b97\u3002 \u8bed\u6cd5 SELECT \u805a\u5408\u51fd\u6570(\u5217\u540d) FROM \u8868\u540d GROUP BY \u5206\u7ec4\u5217\u540d; \u767b\u5f55\u540e\u590d\u5236 \u53c2\u6570 \u805a\u5408\u51fd\u6570\uff1a\u7528\u4e8e\u6267\u884c\u805a\u5408\u8ba1\u7b97\u7684\u51fd\u6570\uff0c\u5982 SUM\u3001COUNT\u3001AVG \u7b49\u3002 \u5217\u540d\uff1a\u7528\u4e8e\u8fdb\u884c\u805a\u5408\u8ba1\u7b97\u7684\u5217\u3002 \u5206\u7ec4\u5217\u540d\uff1a\u7528\u4e8e\u5206\u7ec4\u5408\u5e76\u7684\u5217\u3002 \u7528\u6cd5 GROUP BY \u7528\u6cd5\u5982\u4e0b\uff1a \u6307\u5b9a\u5206\u7ec4\u5217\uff1a\u5728 GROUP BY \u5b50\u53e5\u4e2d\u6307\u5b9a\u8981\u7528\u4e8e\u5206\u7ec4\u7684\u5217\u3002 \u6267\u884c\u805a\u5408\u8ba1\u7b97\uff1a\u4f7f\u7528\u805a\u5408\u51fd\u6570\u5bf9\u6bcf\u4e2a\u7ec4\u7684\u5217\u8fdb\u884c\u8ba1\u7b97\u3002 \u6839\u636e\u7ec4\u83b7\u53d6\u7ed3\u679c\uff1a\u5206\u7ec4\u5b8c\u6210\u540e\uff0cSQL \u67e5\u8be2\u5c06\u8fd4\u56de\u805a\u5408\u8ba1\u7b97\u7684\u7ed3\u679c\uff0c\u5176\u4e2d\u6bcf\u4e00\u884c\u4ee3\u8868\u4e00\u4e2a\u7ec4\u3002 \u793a\u4f8b \u4ee5\u4e0b\u793a\u4f8b\u6f14\u793a\u5982\u4f55\u4f7f\u7528 GROUP BY \u6765\u8ba1\u7b97\u4e0d\u540c\u90e8\u95e8\u7684\u5458\u5de5\u4eba\u6570\uff1a SELECT \u90e8\u95e8, COUNT(*) AS \u4eba\u6570 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-6662","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/6662","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=6662"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/6662\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=6662"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=6662"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=6662"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}