Mongodb Tutorial

You can use the following syntax to list all field names in a collection in MongoDB: Object.keys(db.myCollection.findOne()) This particular example lists every…

You can use the $or operator in MongoDB to query for documents that meet one of multiple criteria. This operator uses the…

You can use the $and operator in MongoDB to query for documents that meet multiple criteria. This operator uses the following basic…

You can use the following methods to rename fields in MongoDB: Method 1: Rename One Field db.collection.updateMany({}, {$rename:{“oldField”:”newField”}}, false, true) Method 2:…

You can use the following methods to find the length of a string in MongoDB and use this string length in queries:…

You can use the following syntax to split a string into an array of substrings in MongoDB: db.myCollection.aggregate([ { $project: { split_field:…

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 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}}}…

You can use the following syntax to group by and count in MongoDB: db.collection.aggregate([ {$group : {_id:”$field_name1″, count:{$sum:”$field_name2″}}} ]) Note that field_name1…