If any of these concepts are new to you, I would suggest you peruse the MongoDB University for free courses about MongoDB. See Create Indexes to Support Your Queries and Use Indexes to Sort Query Results. Sort function in MongoDB accepts a list of values and an integer value 1 or -1 which. Properly indexed, the query could be fast without the need to be sorted in memory, since MongoDB uses the index to perform the sort. MongoDB provides sort() function in order to sort the data in a collection. Lets say I want to display the studentid of all the documents in descending order: To display only a particular field of document, I am using MongoDB Projection. The documents are sorted by count in descending order. Each output document contains two fields: an id field containing the distinct grouping value, and a count field containing the number of documents belonging to that grouping or category. These methods return a Bson object that you can pass to the sort() method of a FindIterable instance or to Aggregates.sort().If you want to learn more about the Aggregates class, see our guide on the Aggregates builder. Groups incoming documents based on the value of a specified expression, then computes the count of documents in each distinct group. One advantage of using cursor sort like this is index use. Syntax of sort () method: 1 is for ascending order and -1 is for descending order. The Sorts class is a builder that provides static factory methods for all sort criteria operators supported by MongoDB. See Date() and Data Types in the mongo Shell Note that if you only specify the field name and don’t specify the direction then it will automatically display the fields in ascending order. Ditto with the create_time sorting order, which is based on string comparison sort.įor richer options with regards to sorting create_time, you need to convert the field into an ISODate() object. In MongoDB, For sorting the fields in python we use the same sort () method and we define the parameter, field name and direction (ascending or descending order). Note that the sorting order on the example above are using string sort, so disabled will come before enabled as it is sorting in alphabetical order. Order by the command is deprecated in MongoDB shell. Different methods to sort the collection in the database are explained briefly. Introduction to order by in MongoDB By operator sorts the result of the query in an ascending and descending order, ascending and descending order is based on the value we mentioned in the query that is 1 is for ascending order and -1 is for descending order. Sorting by status then by create_time: > db.test.find().sort() Sort by Date (Ascending or Descending) in MongoDB Sort by a Date String in MongoDB Sort by Date Using Array in MongoDB In this MongoDB tutorial, the problem of sorting a collection in MongoDB is discussed. Just to add to Veeram's answer, you can use the standard MongoDB sort() method (as per Ian Mercer's comment) as well as aggregation.
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