Database Tutorials

You can use the following syntax to concatenate strings from two fields into a new field in MongoDB: db.myCollection.aggregate([ { $project: {…

You can use the following syntax to replace a specific string in a field in MongoDB: db.myCollection.updateMany( { fieldName: { $regex: /old/…

You can use the following methods to calculate the sum of values in a field in MongoDB: Method 1: Calculate Sum of…

You can use the following syntax to select a random sample of documents from a collection in MongoDB: db.myCollection.aggregate([ { $sample: {…

You can use the $ne operator (which stands for “not equal”) in MongoDB to query for documents where a field is not…

You can use the following operators in MongoDB to perform greater than or less than queries: $lt: Less than $lte: Less than…

You can use the following methods to calculate the average value of a field in MongoDB: Method 1: Calculate Average of Field…

You can use the following syntax to sort documents in MongoDB by multiple fields: db.myCollection.find().sort( { “field1”: 1, “field2”: -1 } )…

You can use the following syntax to calculate the median value in MongoDB: db.teams.find().sort( {“points”:1} ).skip(db.teams.count() / 2).limit(1); Note that in this…

You can use the following syntax to group documents by date in MongoDB: db.collection.aggregate([ {$group:{ _id:{$dateToString:{format: “%Y-%m-%d”, date: “$day”}}, count:{ $sum: 1}}}…