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To update, use UPDATE() and $set. Let us create a collection with documents −> db.demo427.insertOne({"StudentId":101, "StudentName":"Chris Brown"}); { "acknowledged" : true, "insertedId" : ObjectId("5e75e711bbc41e36cc3cae75") } > db.demo427.insertOne({"StudentId":102, "StudentName":"David Miller"}); { "acknowledged" : true, "insertedId" : ObjectId("5e75e71abbc41e36cc3cae76") } > db.demo427.insertOne({"StudentId":103, "StudentName":"John Smith"}); { "acknowledged" : true, "insertedId" : ObjectId("5e75e725bbc41e36cc3cae77") } > db.demo427.insertOne({"StudentId":104, "StudentName":"Carol Taylor"}); { "acknowledged" : true, "insertedId" : ObjectId("5e75e733bbc41e36cc3cae78") }Display all documents from a collection with the help of find() method −> db.demo427.find();This will produce the following output −{ "_id" : ObjectId("5e75e711bbc41e36cc3cae75"), "StudentId" : 101, "StudentName" : "Chris Brown" } { ... Read More
Use $eq operator along with find() to match ID and fetch documents. The $eq specifies equality condition. It matches documents where the value of a field equals the specified value.Let us create a collection with documents −> db.demo426.insert({"Ids":["110", "120", "101"]}); WriteResult({ "nInserted" : 1 }) > db.demo426.insert({"Ids":["100", "201", "401"]}); WriteResult({ "nInserted" : 1 }) > db.demo426.insert({"Ids":["501", "600", "700"]}); WriteResult({ "nInserted" : 1 })Display all documents from a collection with the help of find() method −> db.demo426.find().pretty();This will produce the following output −{ "_id" : ObjectId("5e75e50fbbc41e36cc3cae72"), "Ids" : [ "110", "120", ... Read More
To upsert many documents, use UPSERT() with UPDATE(). Let us create a collection with documents −> db.demo425.insertOne({"Name":"Chris", "Age":21}); { "acknowledged" : true, "insertedId" : ObjectId("5e74ee4fbbc41e36cc3cae6c") } > db.demo425.insertOne({"Name":"David", "Age":23}); { "acknowledged" : true, "insertedId" : ObjectId("5e74ee56bbc41e36cc3cae6d") } > db.demo425.insertOne({"Name":"Chris", "Age":21}); { "acknowledged" : true, "insertedId" : ObjectId("5e74ee57bbc41e36cc3cae6e") } > db.demo425.insertOne({"Name":"Chris", "Age":21}); { "acknowledged" : true, "insertedId" : ObjectId("5e74ee5cbbc41e36cc3cae6f") }Display all documents from a collection with the help of find() method −> db.demo425.find();This will produce the following output −{ "_id" : ObjectId("5e74ee4fbbc41e36cc3cae6c"), "Name" : "Chris", "Age" : 21 } { "_id" : ObjectId("5e74ee56bbc41e36cc3cae6d"), ... Read More
To extract a MongoDB document with a specific string, use $match in MongoDB. Let us create a collection with documents −> db.demo424.insert( ... { ... ... "Information" : [ ... { ... id:10, ... Name:"Chris" ... }, ... { ... id:11, ... Name:"David" ... } ... ] ... } ... ) WriteResult({ ... Read More
To speed up the $group phase, use $group along with aggregation. Let us see an example and create a collection with documents −> db.demo423.insertOne({"Information":[101, 110, 87, 110, 98, 115, 101, 115, 89, 115]}); { "acknowledged" : true, "insertedId" : ObjectId("5e73a60e9822da45b30346e6") }Display all documents from a collection with the help of find() method −> db.demo423.find();This will produce the following output −{ "_id" : ObjectId("5e73a60e9822da45b30346e6"), "Information" : [ 101, 110, 87, 110, 98, 115, 101, 115, 89, 115 ] }Following is the query to speed up $group phase in aggregation −> db.demo423.aggregate([ ... { ... $project: ... Read More
For exact match, set the values to be matched inside MongoDB $in(). Let us first create a collection with documents −> db.demo422.insertOne({"Name":"Chris", "Marks":34}); { "acknowledged" : true, "insertedId" : ObjectId("5e73a4059822da45b30346e1") } > db.demo422.insertOne({"Name":"Chris", "Marks":56}); { "acknowledged" : true, "insertedId" : ObjectId("5e73a40a9822da45b30346e2") } > db.demo422.insertOne({"Name":"David", "Marks":78}); { "acknowledged" : true, "insertedId" : ObjectId("5e73a4149822da45b30346e3") } > db.demo422.insertOne({"Name":"Sam", "Marks":45}); { "acknowledged" : true, "insertedId" : ObjectId("5e73a41e9822da45b30346e4") } > db.demo422.insertOne({"Name":"David", "Marks":89}); { "acknowledged" : true, "insertedId" : ObjectId("5e73a4239822da45b30346e5") }Display all documents from a collection with the help of find() method −> db.demo422.find();This will produce ... Read More
To insert date in MongoDB, use Date(). Let us create a collection with documents −> db.demo421.insert({"DueDate":new Date(Date.now())}); WriteResult({ "nInserted" : 1 }) > db.demo421.insert({"DueDate":new Date("2020-01-15")}); WriteResult({ "nInserted" : 1 }) > db.demo421.insert({"DueDate":new Date("2018-12-31")}); WriteResult({ "nInserted" : 1 })Display all documents from a collection with the help of find() method −> db.demo421.find();This will produce the following output −{ "_id" : ObjectId("5e73a2ec9822da45b30346de"), "DueDate" : ISODate("2020-03-19T16:50:52.746Z") } { "_id" : ObjectId("5e73a2fb9822da45b30346df"), "DueDate" : ISODate("2020-01-15T00:00:00Z") } { "_id" : ObjectId("5e73a3079822da45b30346e0"), "DueDate" : ISODate("2018-12-31T00:00:00Z") }Read More
To combine unique items from array, use aggregate() in MongoDB. Let us create a collection with documents −> db.demo420.insert( ... { ... ... "details" : [ ... { ... "Value1":10, ... "Value2":20, ... "Value3":30 ... } ... ] ... } ... ) WriteResult({ "nInserted" : 1 }) > db.demo420.insert( ... { ... ... "Info" : [ ... { ... Read More
Let us first create a collection with documents −>db.demo419.insertOne({"ProductInformation":[{"ProductName":"Product-1", "ProductPrice":500}, {"ProductName":"Product-2", "ProductPrice":600}]}); { "acknowledged" : true, "insertedId" : ObjectId("5e724762b912067e57771ae8") }Display all documents from a collection with the help of find() method −> db.demo419.find();This will produce the following output −{ "_id" : ObjectId("5e724762b912067e57771ae8"), "ProductInformation" : [ { "ProductName" : "Product-1", "ProductPrice" : 500 }, { "ProductName" : "Product-2", "ProductPrice" : 600 } ] }Following is the query to update object in array with a specific key −> db.demo419.update({'ProductInformation.ProductName' : "Product-1" }, { $set : { 'ProductInformation.$.ProductPrice' : 1250}}); WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }Display ... Read More
For this, use aggregate(). Let us first create a collection with documents −> db.demo418.insertOne( ... { ... "details":[ ... { ... "CountryName":"US", ... "Marks":45 ... }, ... { ... "CountryName":"US", ... "Marks":56 ... }, ... ... ], ... "Name":"John" ... } ... ); { "acknowledged" : true, ... Read More