mongodb last
Returns the value that results from applying an expression to the last document in a group of documents that share the same group by a field. Only meaningful ... ,2020年1月20日 — New in version 4.4. Returns the last element in an array. Disambiguation. The following page describes the array element operator $last .
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 mongodb last 相關參考資料
$arrayElemAt (aggregation) — MongoDB Manual
The following example returns the first and last element in the favorites array: copy. copied. db.users.aggregate([ $project: name: 1, first: $arrayElemAt: ... https://docs.mongodb.com $last (aggregation accumulator) — MongoDB Manual
Returns the value that results from applying an expression to the last document in a group of documents that share the same group by a field. Only meaningful ... https://docs.mongodb.com $last (aggregation) — MongoDB Manual
2020年1月20日 — New in version 4.4. Returns the last element in an array. Disambiguation. The following page describes the array element operator $last . https://docs.mongodb.com Getting last row in mongodb - Stack Overflow
If you want to get last record inserted in the table, then sort by ObjectId in descending order: sorting on an _id field that stores ObjectId values is roughly ... https://stackoverflow.com How to get the last N records in mongodb? - Stack Overflow
2014年3月6日 — If I understand your question, you need to sort in ascending order. Assuming you have some id or date field called "x" you would do ... .sort() ... https://stackoverflow.com MongoDB get first and last document in aggregate query ...
Well you need $group but you can simply use a constant (e.g. null , see the docs) for its id so that it results in a single group. $$ROOT then refers to the ... https://stackoverflow.com MongoDB query to find last object in collection? - Tutorialspoint
2020年3月31日 — To find last object in collection, at first sort() to sort the values. Use limit() to get number of values i.e. if you want only the last object, then use ... https://www.tutorialspoint.com Mongodb v3.6 中文文档- $last (aggregation) | Docs4dev
Definition. $last. 返回将表达式应用于在一组按字段共享同一组文档的最后一个文档中得 ... https://www.docs4dev.com MongoDb, query the last, and group by - Stack Overflow
2015年8月21日 — You can always use $$ROOT to return the whole document on the grouping boundary: db.collection.aggregate([ "$group": "_id": "$zone._id" ... https://stackoverflow.com pop - MongoDB Documentation
Remove the Last Item of an Array¶. Given the following document in a collection students : copy. copied. ... https://docs.mongodb.com |