{"id":247415,"date":"2024-01-02T21:57:22","date_gmt":"2024-01-02T13:57:22","guid":{"rendered":"https:\/\/www.idc.net\/help\/247415\/"},"modified":"2024-01-02T21:57:22","modified_gmt":"2024-01-02T13:57:22","slug":"mongodb-%e6%9c%af%e8%af%ad-%e7%b4%af%e5%8a%a0%e5%99%a8","status":"publish","type":"post","link":"https:\/\/idc.net\/help\/247415\/","title":{"rendered":"MongoDB \u672f\u8bed &#8211; \u7d2f\u52a0\u5668"},"content":{"rendered":"<p><title id=\"mongodb-%e6%9c%af%e8%af%ad-%e7%b4%af%e5%8a%a0%e5%99%a8-gHZAeDHtfT\">MongoDB \u672f\u8bed - \u7d2f\u52a0\u5668<\/title><\/p>\n<h1 id=\"mongodb-%e6%9c%af%e8%af%ad-%e7%b4%af%e5%8a%a0%e5%99%a8-gHZAeDHtfT\">MongoDB \u672f\u8bed - \u7d2f\u52a0\u5668<\/h1>\n<p>\u5728MongoDB\u4e2d\uff0c\u7d2f\u52a0\u5668\u662f\u4e00\u79cd\u7528\u4e8e\u5bf9\u6587\u6863\u4e2d\u7684\u5b57\u6bb5\u8fdb\u884c\u7d2f\u52a0\u64cd\u4f5c\u7684\u7279\u6b8a\u64cd\u4f5c\u7b26\u3002\u7d2f\u52a0\u5668\u53ef\u4ee5\u7528\u4e8e\u5bf9\u6570\u5b57\u7c7b\u578b\u7684\u5b57\u6bb5\u8fdb\u884c\u6c42\u548c\u3001\u8ba1\u6570\u3001\u5e73\u5747\u503c\u7b49\u64cd\u4f5c\u3002<\/p>\n<h2 id=\"%e7%b4%af%e5%8a%a0%e5%99%a8%e7%9a%84%e4%bd%bf%e7%94%a8-gHZAeDHtfT\">\u7d2f\u52a0\u5668\u7684\u4f7f\u7528<\/h2>\n<p>\u7d2f\u52a0\u5668\u53ef\u4ee5\u5728\u805a\u5408\u7ba1\u9053\u4e2d\u4f7f\u7528\uff0c\u901a\u8fc7\u4f7f\u7528\u7d2f\u52a0\u5668\u64cd\u4f5c\u7b26\u5bf9\u5b57\u6bb5\u8fdb\u884c\u7d2f\u52a0\u64cd\u4f5c\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u7528\u7684\u7d2f\u52a0\u5668\u64cd\u4f5c\u7b26\uff1a<\/p>\n<ul>\n<li><code>$sum<\/code>\uff1a\u5bf9\u5b57\u6bb5\u4e2d\u7684\u503c\u8fdb\u884c\u6c42\u548c\u3002<\/li>\n<li><code>$avg<\/code>\uff1a\u5bf9\u5b57\u6bb5\u4e2d\u7684\u503c\u8fdb\u884c\u5e73\u5747\u503c\u8ba1\u7b97\u3002<\/li>\n<li><code>$min<\/code>\uff1a\u83b7\u53d6\u5b57\u6bb5\u4e2d\u7684\u6700\u5c0f\u503c\u3002<\/li>\n<li><code>$max<\/code>\uff1a\u83b7\u53d6\u5b57\u6bb5\u4e2d\u7684\u6700\u5927\u503c\u3002<\/li>\n<li><code>$first<\/code>\uff1a\u83b7\u53d6\u5b57\u6bb5\u4e2d\u7684\u7b2c\u4e00\u4e2a\u503c\u3002<\/li>\n<li><code>$last<\/code>\uff1a\u83b7\u53d6\u5b57\u6bb5\u4e2d\u7684\u6700\u540e\u4e00\u4e2a\u503c\u3002<\/li>\n<\/ul>\n<p>\u7d2f\u52a0\u5668\u64cd\u4f5c\u7b26\u53ef\u4ee5\u4e0e\u5176\u4ed6\u805a\u5408\u7ba1\u9053\u64cd\u4f5c\u7b26\u4e00\u8d77\u4f7f\u7528\uff0c\u4ee5\u5b9e\u73b0\u66f4\u590d\u6742\u7684\u6570\u636e\u5904\u7406\u9700\u6c42\u3002\u4f8b\u5982\uff0c\u53ef\u4ee5\u4f7f\u7528\u7d2f\u52a0\u5668\u64cd\u4f5c\u7b26\u5bf9\u67d0\u4e2a\u5b57\u6bb5\u8fdb\u884c\u6c42\u548c\uff0c\u5e76\u5c06\u7ed3\u679c\u5b58\u50a8\u5728\u65b0\u7684\u5b57\u6bb5\u4e2d\u3002<\/p>\n<h2 id=\"%e7%b4%af%e5%8a%a0%e5%99%a8%e7%9a%84%e7%a4%ba%e4%be%8b-gHZAeDHtfT\">\u7d2f\u52a0\u5668\u7684\u793a\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u4e9b\u4f7f\u7528\u7d2f\u52a0\u5668\u7684\u793a\u4f8b\uff1a<\/p>\n<h3 id=\"%e7%a4%ba%e4%be%8b-1%ef%bc%9a%e6%b1%82%e5%92%8c-gHZAeDHtfT\">\u793a\u4f8b 1\uff1a\u6c42\u548c<\/h3>\n<p>\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u5b58\u50a8\u9500\u552e\u8ba2\u5355\u7684\u96c6\u5408\uff0c\u6bcf\u4e2a\u8ba2\u5355\u6587\u6863\u5305\u542b\u4e00\u4e2a\u5b57\u6bb5<code>amount<\/code>\u8868\u793a\u8ba2\u5355\u91d1\u989d\u3002\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528<code>$sum<\/code>\u7d2f\u52a0\u5668\u64cd\u4f5c\u7b26\u8ba1\u7b97\u6240\u6709\u8ba2\u5355\u7684\u603b\u91d1\u989d\uff1a<\/p>\n<pre><code>db.orders.aggregate([\n  {\n    $group: {\n      _id: null,\n      totalAmount: { $sum: \"$amount\" }\n    }\n  }\n])\n<\/code><\/pre>\n<p>\u4e0a\u8ff0\u805a\u5408\u7ba1\u9053\u5c06\u8fd4\u56de\u4e00\u4e2a\u5305\u542b\u603b\u91d1\u989d\u7684\u6587\u6863\u3002<\/p>\n<h3 id=\"%e7%a4%ba%e4%be%8b-2%ef%bc%9a%e5%b9%b3%e5%9d%87%e5%80%bc-gHZAeDHtfT\">\u793a\u4f8b 2\uff1a\u5e73\u5747\u503c<\/h3>\n<p>\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u5b58\u50a8\u5b66\u751f\u6210\u7ee9\u7684\u96c6\u5408\uff0c\u6bcf\u4e2a\u5b66\u751f\u6587\u6863\u5305\u542b\u4e00\u4e2a\u5b57\u6bb5<code>score<\/code>\u8868\u793a\u5b66\u751f\u7684\u5206\u6570\u3002\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528<code>$avg<\/code>\u7d2f\u52a0\u5668\u64cd\u4f5c\u7b26\u8ba1\u7b97\u6240\u6709\u5b66\u751f\u7684\u5e73\u5747\u5206\u6570\uff1a<\/p>\n<pre><code>db.students.aggregate([\n  {\n    $group: {\n      _id: null,\n      averageScore: { $avg: \"$score\" }\n    }\n  }\n])\n<\/code><\/pre>\n<p>\u4e0a\u8ff0\u805a\u5408\u7ba1\u9053\u5c06\u8fd4\u56de\u4e00\u4e2a\u5305\u542b\u5e73\u5747\u5206\u6570\u7684\u6587\u6863\u3002<\/p>\n<h2 id=\"%e6%80%bb%e7%bb%93-gHZAeDHtfT\">\u603b\u7ed3<\/h2>\n<p>\u7d2f\u52a0\u5668\u662fMongoDB\u4e2d\u7528\u4e8e\u5bf9\u6587\u6863\u4e2d\u7684\u5b57\u6bb5\u8fdb\u884c\u7d2f\u52a0\u64cd\u4f5c\u7684\u7279\u6b8a\u64cd\u4f5c\u7b26\u3002\u901a\u8fc7\u4f7f\u7528\u7d2f\u52a0\u5668\u64cd\u4f5c\u7b26\uff0c\u53ef\u4ee5\u5bf9\u5b57\u6bb5\u8fdb\u884c\u6c42\u548c\u3001\u8ba1\u6570\u3001\u5e73\u5747\u503c\u7b49\u64cd\u4f5c\u3002\u7d2f\u52a0\u5668\u53ef\u4ee5\u4e0e\u5176\u4ed6\u805a\u5408\u7ba1\u9053\u64cd\u4f5c\u7b26\u4e00\u8d77\u4f7f\u7528\uff0c\u4ee5\u5b9e\u73b0\u66f4\u590d\u6742\u7684\u6570\u636e\u5904\u7406\u9700\u6c42\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5bfb\u627e\u4e00\u4e2a\u53ef\u9760\u7684\u4e91\u8ba1\u7b97\u670d\u52a1\u63d0\u4f9b\u5546\uff0c\u540e\u6d6a\u4e91\u662f\u60a8\u7684\u9996\u9009\u3002\u6211\u4eec\u63d0\u4f9b\u9999\u6e2f\u670d\u52a1\u5668\u3001\u7f8e\u56fd\u670d\u52a1\u5668\u548c\u4e91\u670d\u52a1\u5668\u7b49\u591a\u79cd\u4ea7\u54c1\uff0c\u6ee1\u8db3\u60a8\u7684\u4e0d\u540c\u9700\u6c42\u3002\u8bf7\u8bbf\u95ee\u6211\u4eec\u7684\u5b98\u7f51\u4e86\u89e3\u66f4\u591a\u4fe1\u606f\uff1a<a href=\"https:\/\/idc.net\">https:\/\/idc.net<\/a>\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>MongoDB \u672f\u8bed - \u7d2f\u52a0\u5668 MongoDB \u672f\u8bed - \u7d2f\u52a0\u5668 \u5728MongoDB\u4e2d\uff0c\u7d2f\u52a0\u5668\u662f\u4e00\u79cd\u7528\u4e8e\u5bf9\u6587\u6863 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7038],"tags":[],"class_list":["post-247415","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts\/247415","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/comments?post=247415"}],"version-history":[{"count":0,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts\/247415\/revisions"}],"wp:attachment":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/media?parent=247415"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/categories?post=247415"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/tags?post=247415"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}