{"id":10948,"date":"2013-10-04T20:35:56","date_gmt":"2013-10-04T15:05:56","guid":{"rendered":"http:\/\/www.tothenew.com\/blog\/?p=10948"},"modified":"2016-12-19T15:31:03","modified_gmt":"2016-12-19T10:01:03","slug":"group-by-in-mongodbwith-group","status":"publish","type":"post","link":"https:\/\/www.tothenew.com\/blog\/group-by-in-mongodbwith-group\/","title":{"rendered":"Group By in MongoDB(with $group)"},"content":{"rendered":"

MongoDB<\/strong> provides a rich set of aggregation<\/strong>. $group<\/strong> is one of them, with the help of $group<\/strong>, we can group<\/strong> documents (similar as group By<\/strong> in SQL<\/strong>). Lets understand by an example:<\/p>\n

Suppose we have following collection of blogs:
\n[js]
\n{ userId:1, name:”Suroor”, title:”AngularJS: Getting started with Directive”, rating:3}
\n{ userId:2, name:”Amit”, title:”AngularJS: Getting started with Directive”, rating:5}
\n{ userId:3, name:”PI”, title:”Prototype in Javascript”, rating:4}
\n{ userId:2, name:”Amit”, title:”this keyword in Javascript”, rating:5}
\n[\/js]
\nAnd now we want to group<\/strong> all the blogs by userId and rating greater then 3:
\n[js]
\ndb.blogs.aggregate([{$match:{rating:{$gt:3}}}, {$group:{ _id: ‘$userId’, title: { $push: ‘$title’}}}]);
\n[\/js]
\nThis will return grouped<\/strong> result of all the blogs with id and title whose rating is greater then 3<\/strong>. Here $match<\/strong> will match the condition, $group<\/strong> groups all the documents by field-name which is provided as _id and $push<\/strong> will add the title into result.<\/p>\n

OUTPUT:<\/strong>
\n[js]
\n{
\n\t“result” : [
\n\t\t{
\n\t\t\t“_id” : 3,
\n\t\t\t“title” : [
\n\t\t\t\t“Prototype in Javascript”
\n\t\t\t]
\n\t\t},
\n\t\t{
\n\t\t\t“_id” : 2,
\n\t\t\t“title” : [
\n\t\t\t\t“AngularJS: Getting started with Directive”,
\n\t\t\t\t“this keyword in Javascript”
\n\t\t\t]
\n\t\t}
\n\t],
\n\t“ok” : 1
\n}
\n[\/js]<\/p>\n

Amit Kumar
\namit.kumar@intelligrape.com<\/a>
\nin.linkedin.com\/in\/amitkumar0110
\ntwitter.com\/amit_kumar0110
\nMore Blogs by Me<\/a><\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

MongoDB provides a rich set of aggregation. $group is one of them, with the help of $group, we can group documents (similar as group By in SQL). Lets understand by an example: Suppose we have following collection of blogs: [js] { userId:1, name:”Suroor”, title:”AngularJS: Getting started with Directive”, rating:3} { userId:2, name:”Amit”, title:”AngularJS: Getting started […]<\/p>\n","protected":false},"author":52,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"iawp_total_views":1},"categories":[1],"tags":[1223,1149,1151,4846],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/10948"}],"collection":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/users\/52"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/comments?post=10948"}],"version-history":[{"count":0,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/10948\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/media?parent=10948"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/categories?post=10948"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/tags?post=10948"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}