To get the count of studentData for each Department db.getCollection ('student').aggregate ( [ { $lookup: { from:"department", localField:"branch", foreignField:"_id", as:"branch" } }, { $group: { _id:"$branch", "numOfStudent": {$sum:1}, "listOfStudents": {$push:"$name"} } } ] ) This will give you something like this: Web10 feb. 2024 · Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about Teams
Array : How to find count in mongodb using $in and using …
WebArray : How to find count in mongodb using $in and using greater than and lesser than? Delphi 29.7K subscribers Subscribe No views 1 minute ago Array : How to find count in mongodb using... WebThere is a special case when the pipeline stages are $lookup -> $unwind -> $match and the condition in $match (in succession ) and $match refers to the array from $lookup where … oem odm わかりやすく
NodeJS : How to speed up MongoDB count() Queries? - YouTube
Web13 apr. 2024 · Thank you for your answer and help. But this query would return a number of documents that were joined and I instead have to count the number of the documents that have a corresponding customerId field for each customer and only have a field with that number in a customer object, without adding the document objects themselves. My … Web5,970 7 55 107 Add a comment 2 Answers Sorted by: 15 Total count will always be a one-document result so you need $facet to run mutliple aggregation pipelines and then merge results. Let's say your regular pipeline contains simple $project and you want to merge it's results with $count. You can run below aggregation: WebMongoDB: How to realize an lookup dictionary for checking text user3142695 2016-12-04 08:19:36 176 1 javascript / mongodb / meteor oemとは 化粧品