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For nested queries, let us first create a collection with documents −> db.demo492.insertOne({ ... "ProductDetails" : ... { ... "StockDetails" : [ ... { "ProductName" : "Product-1" }, ... {"ProductName" : "Product-2"}, ... { "ProductName" : "Product-3"} ... ... ] ... ... } ... }); { "acknowledged" : true, "insertedId" : ObjectId("5e849db8b0f3fa88e22790c2") } > > > > db.demo492.insertOne({ ... "ProductDetails" : ... { ... "StockDetails" : [ ... ... Read More
To match date, use $match along with aggregate(). Let us create a collection with documents −> db.demo491.insertOne({"ShippingDate":new ISODate("2020-01-10")});{ "acknowledged" : true, "insertedId" : ObjectId("5e849a09b0f3fa88e22790be") } > db.demo491.insertOne({"ShippingDate":new ISODate("2020-02-21")});{ "acknowledged" : true, "insertedId" : ObjectId("5e849a0eb0f3fa88e22790bf") } > db.demo491.insertOne({"ShippingDate":new ISODate("2020-03-23")});{ "acknowledged" : true, "insertedId" : ObjectId("5e849a1db0f3fa88e22790c0") } > db.demo491.insertOne({"ShippingDate":new ISODate()});{ "acknowledged" : true, "insertedId" : ObjectId("5e849a28b0f3fa88e22790c1") }Display all documents from a collection with the help of find() method −> db.demo491.find();This will produce the following output −{ "_id" : ObjectId("5e849a09b0f3fa88e22790be"), "ShippingDate" : ISODate("2020-01- 10T00:00:00Z") } { "_id" : ObjectId("5e849a0eb0f3fa88e22790bf"), "ShippingDate" : ISODate("2020-02- 21T00:00:00Z") } { ... Read More
For all elements of a field in MongoDB, use find() and in that, use $elemMatch. The $elemMatch operator matches documents that contain an array field with at least one element that matches all the specified query criteria.Let us create a collection with documents −> db.demo624.insertOne({"ListOfName":["John", "Chris", "David", "Bob"]}); { "acknowledged" : true, "insertedId" : ObjectId("5e9ab3ff6c954c74be91e6a5") } > db.demo624.insertOne({"ListOfName":["John", "Chris"]}); { "acknowledged" : true, "insertedId" : ObjectId("5e9ab4026c954c74be91e6a6") } > db.demo624.insertOne({"ListOfName":["John", "Chris", "Carol"]}); { "acknowledged" : true, "insertedId" : ObjectId("5e9ab4076c954c74be91e6a7") } > db.demo624.insertOne({"ListOfName":["John", "Chris", "Bob"]}); { "acknowledged" : true, "insertedId" : ObjectId("5e9ab40e6c954c74be91e6a8") } > ... Read More
Yes, to search an array of objects, use $unwind in MongoDB aggregate(). To match, use $match. Let us create a collection with documents −> db.demo623.insertOne( ... { ... _id:1, ... details:[ ... { ... Name:"Chris" ... }, ... { ... DueDate:new ISODate("2020-01-10") ... }, ... { ... CountryName:"US" ... } ... ... Read More
To fix this, use $dateFromString in MongoDB aggregate(). The $dateFromString converts a date/time string to a date object.Let us create a collection with documents −> db.demo619.insertOne({"DueDate":"10-10-2020"}); { "acknowledged" : true, "insertedId" : ObjectId("5e99d7846c954c74be91e69e") } > db.demo619.insertOne({"DueDate":"12-01-2019"}); { "acknowledged" : true, "insertedId" : ObjectId("5e99d7996c954c74be91e69f") } > db.demo619.insertOne({"DueDate":"28-10-2010"}); { "acknowledged" : true, "insertedId" : ObjectId("5e99d7ab6c954c74be91e6a0") }Display all documents from a collection with the help of find() method −> db.demo619.find();This will produce the following output −{ "_id" : ObjectId("5e99d7846c954c74be91e69e"), "DueDate" : "10-10-2020" } { "_id" : ObjectId("5e99d7996c954c74be91e69f"), "DueDate" : "12-01-2019" } { "_id" : ObjectId("5e99d7ab6c954c74be91e6a0"), "DueDate" : ... Read More
Remove document using remove(), whose value is matched with $eq from a MongoDB collection. The $eq operator matches documents where the value of a field equals the specified value.Let us create a collection with documents −> db.demo626.insertOne({id:1, "Name":"Chris"}); { "acknowledged" : true, "insertedId" : ObjectId("5e9ac6376c954c74be91e6ae") } > db.demo626.insertOne({id:2, "Name":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5e9ac63e6c954c74be91e6af") } > db.demo626.insertOne({id:3, "Name":"Bob"}); { "acknowledged" : true, "insertedId" : ObjectId("5e9ac6436c954c74be91e6b0") } > db.demo626.insertOne({id:4, "Name":"Mike"}); { "acknowledged" : true, "insertedId" : ObjectId("5e9ac6486c954c74be91e6b1") }Display all documents from a collection with the help of find() method −> db.demo626.find();This ... Read More
To redirect to another webpage using JavaScript, the code is as follows −Example Live Demo Redirect to a Webpage Example Redirect Click the above button to Redirect to another Webpage document .querySelector(".redirectBtn") .addEventListener("click", redirectFunction); function redirectFunction() { location.href("https://tutorialspoint.com/"); } OutputThe above code will produce the following output −On clicking the “Redirect” button we will be redirected to a new site −
To create a speed converter with HTML and JavaScript, the code is as follows −Example Live Demo body { font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif; } input, span { font-size: 20px; } Speed Converter Type speed in Kilometer per hour to convert it into meter per hour Kilometer Per Hour Meters Per second: function KmphtoMphConverter(speed) { document.querySelector(".metersPerSecond").innerHTML = speed * 0.277778; } OutputThe above code will produce the following output −On entering some speed in kph −
To create a length converter with HTML and JavaScript, the code is as follows −Example Live Demo body{ font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; } input,span{ font-size: 20px; } Length Converter Type length in Kilometers to convert it into meters Kilometers Meters: function KmtoMConverter(length) { document.querySelector(".meters").innerHTML=length*1000; } OutputThe above code will produce the following output −On entering length in kilometers −
To create a temperature converter with HTML and JavaScript, the code is as follows −Example Live Demo body{ font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; } input,span{ font-size: 20px; } Temperature Converter Type Temperature in celcius to convert it into fahrenheit Celcius Fahrenheit: function CtoFConverter(temp) { document.querySelector(".fahrenheit").innerHTML=(temp-32)/1.8; } OutputThe above code will produce the following output −On entering temperature in celcius −