{"id":6747,"date":"2024-11-14T15:34:51","date_gmt":"2024-11-14T07:34:51","guid":{"rendered":"https:\/\/fwq.ai\/blog\/6747\/"},"modified":"2024-11-14T15:34:51","modified_gmt":"2024-11-14T07:34:51","slug":"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8mysql%e6%9f%a5%e8%af%a2%e7%89%b9%e5%ae%9a%e6%97%a5%e6%9c%9f%e7%9a%84%e4%ba%a7%e5%93%81%e6%80%bb%e9%94%80%e9%87%8f%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/6747\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528MySQL\u67e5\u8be2\u7279\u5b9a\u65e5\u671f\u7684\u4ea7\u54c1\u603b\u9500\u91cf\uff1f"},"content":{"rendered":"<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/001\/246\/273\/172985905299000.jpg\" class=\"aligncenter\" title=\"\u5982\u4f55\u4f7f\u7528MySQL\u67e5\u8be2\u7279\u5b9a\u65e5\u671f\u7684\u4ea7\u54c1\u603b\u9500\u91cf\uff1f\u63d2\u56fe\" alt=\"\u5982\u4f55\u4f7f\u7528MySQL\u67e5\u8be2\u7279\u5b9a\u65e5\u671f\u7684\u4ea7\u54c1\u603b\u9500\u91cf\uff1f\u63d2\u56fe\" \/><\/p>\n<p><strong>\u5173\u4e8e\u7684\u6570\u636e\u67e5\u8be2\u57fa\u672c\u64cd\u4f5c<\/strong><\/p>\n<p>\u5728\u6570\u636e\u5206\u6790\u548c\u5904\u7406\u4e2d\uff0c\u6570\u636e\u67e5\u8be2\u662f\u4e00\u4e2a\u57fa\u672c\u64cd\u4f5c\u3002\u672c\u6587\u5c06\u4ecb\u7ecd\u5982\u4f55\u5728mysql\u4e2d\u6267\u884c\u8fd9\u6837\u7684\u67e5\u8be2\u3002<\/p>\n<p>\u8003\u8651\u4ee5\u4e0b\u793a\u4f8b\uff0c\u5176\u4e2d\u6211\u4eec\u5e0c\u671b\u4ece\u4e00\u4e2a\u5305\u542b\u65e5\u671f\u3001\u4ea7\u54c1\u548c\u9500\u91cf\u7684\u8868\u683c\u4e2d\uff0c\u63d0\u53d6\u6bcf\u79cd\u4ea7\u54c1\u5728\u4e24\u4e2a\u4e0d\u540c\u65e5\u671f\uff082021-1-1\u548c2021-1-2\uff09\u7684\u603b\u9500\u91cf\u3002<\/p>\n<p><strong>\u5b9e\u73b0<\/strong><\/p>\n<p>\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0bsql\u8bed\u53e5\u5b8c\u6210\u6b64\u4efb\u52a1\uff1a<\/p>\n<pre>SELECT \u4ea7\u54c1 as \u4ea7\u54c1\u9500\u91cf,\nsum(case \u65e5\u671f when '2021-1-1' then \u9500\u91cf else 0 end) as '2021-1-1', \nsum(case \u65e5\u671f when '2021-1-2' then \u9500\u91cf else 0 end) as '2021-1-2' \nFROM mytable group by \u4ea7\u54c1;<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p><strong>\u8bed\u53e5\u5206\u6790<\/strong><\/p>\n<ul>\n<li>select \u8bed\u53e5\u6307\u5b9a\u8981\u63d0\u53d6\u7684\u5217\uff0c\u5373\u4ea7\u54c1\u9500\u91cf\u30012021-1-1\u548c2021-1-2\u7684\u9500\u91cf\u3002<\/li>\n<li>case \u8868\u8fbe\u5f0f\u7528\u4e8e\u6761\u4ef6\u6c42\u548c\uff0c\u6839\u636e\u65e5\u671f\u5217\u7684\u503c\u8ba1\u7b97\u9500\u91cf\u3002<\/li>\n<li>group by \u5b50\u53e5\u5bf9\u7ed3\u679c\u6309\u4ea7\u54c1\u5206\u7ec4\uff0c\u6c47\u603b\u6bcf\u4e2a\u4ea7\u54c1\u7684\u9500\u91cf\u3002<\/li>\n<\/ul>\n<p><strong>\u5176\u4ed6\u5b9e\u73b0\u65b9\u6cd5<\/strong><\/p>\n<p>\u8fd8\u53ef\u4ee5\u4f7f\u7528\u5176\u4ed6\u65b9\u6cd5\u5b9e\u73b0\u6b64\u67e5\u8be2\uff0c\u4f8b\u5982\uff1a<\/p>\n<ul>\n<li>left join \u65b9\u6cd5\uff0c\u7c7b\u4f3c\u4e8e\u95ee\u9898\u7684\u793a\u4f8b\u4ee3\u7801<\/li>\n<li>pivot \u8868\u51fd\u6570\uff0c\u7528\u4e8e\u5c06\u6570\u636e\u4ece\u884c\u683c\u5f0f\u8f6c\u6362\u4e3a\u5217\u683c\u5f0f<\/li>\n<\/ul>\n<p>\u4ee5\u4e0a\u5c31\u662f\u5982\u4f55\u4f7f\u7528MySQL\u67e5\u8be2\u7279\u5b9a\u65e5\u671f\u7684\u4ea7\u54c1\u603b\u9500\u91cf\uff1f\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":"<p>\u5173\u4e8e\u7684\u6570\u636e\u67e5\u8be2\u57fa\u672c\u64cd\u4f5c \u5728\u6570\u636e\u5206\u6790\u548c\u5904\u7406\u4e2d\uff0c\u6570\u636e\u67e5\u8be2\u662f\u4e00\u4e2a\u57fa\u672c\u64cd\u4f5c\u3002\u672c\u6587\u5c06\u4ecb\u7ecd\u5982\u4f55\u5728mysql\u4e2d\u6267\u884c\u8fd9\u6837\u7684\u67e5\u8be2\u3002 \u8003\u8651\u4ee5\u4e0b\u793a\u4f8b\uff0c\u5176\u4e2d\u6211\u4eec\u5e0c\u671b\u4ece\u4e00\u4e2a\u5305\u542b\u65e5\u671f\u3001\u4ea7\u54c1\u548c\u9500\u91cf\u7684\u8868\u683c\u4e2d\uff0c\u63d0\u53d6\u6bcf\u79cd\u4ea7\u54c1\u5728\u4e24\u4e2a\u4e0d\u540c\u65e5\u671f\uff082021-1-1\u548c2021-1-2\uff09\u7684\u603b\u9500\u91cf\u3002 \u5b9e\u73b0 \u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0bsql\u8bed\u53e5\u5b8c\u6210\u6b64\u4efb\u52a1\uff1a SELECT \u4ea7\u54c1 as \u4ea7\u54c1\u9500\u91cf, sum(case \u65e5\u671f when &#8216;2021-1-1&#8217; then \u9500\u91cf else 0 end) as &#8216;2021-1-1&#8217;, sum(case \u65e5\u671f when &#8216;2021-1-2&#8217; then \u9500\u91cf else 0 end) as &#8216;2021-1-2&#8217; FROM mytable group by \u4ea7\u54c1; \u767b\u5f55\u540e\u590d\u5236 \u8bed\u53e5\u5206\u6790 select \u8bed\u53e5\u6307\u5b9a\u8981\u63d0\u53d6\u7684\u5217\uff0c\u5373\u4ea7\u54c1\u9500\u91cf\u30012021-1-1\u548c2021-1-2\u7684\u9500\u91cf\u3002 case \u8868\u8fbe\u5f0f\u7528\u4e8e\u6761\u4ef6\u6c42\u548c\uff0c\u6839\u636e\u65e5\u671f\u5217\u7684\u503c\u8ba1\u7b97\u9500\u91cf\u3002 group by \u5b50\u53e5\u5bf9\u7ed3\u679c\u6309\u4ea7\u54c1\u5206\u7ec4\uff0c\u6c47\u603b\u6bcf\u4e2a\u4ea7\u54c1\u7684\u9500\u91cf\u3002 \u5176\u4ed6\u5b9e\u73b0\u65b9\u6cd5 \u8fd8\u53ef\u4ee5\u4f7f\u7528\u5176\u4ed6\u65b9\u6cd5\u5b9e\u73b0\u6b64\u67e5\u8be2\uff0c\u4f8b\u5982\uff1a left join \u65b9\u6cd5\uff0c\u7c7b\u4f3c\u4e8e\u95ee\u9898\u7684\u793a\u4f8b\u4ee3\u7801 pivot \u8868\u51fd\u6570\uff0c\u7528\u4e8e\u5c06\u6570\u636e\u4ece\u884c\u683c\u5f0f\u8f6c\u6362\u4e3a\u5217\u683c\u5f0f \u4ee5\u4e0a\u5c31\u662f\u5982\u4f55\u4f7f\u7528MySQL\u67e5\u8be2\u7279\u5b9a\u65e5\u671f\u7684\u4ea7\u54c1\u603b\u9500\u91cf\uff1f\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},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-6747","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/6747","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=6747"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/6747\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=6747"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=6747"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=6747"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}