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To create CSS3 Transition Effects, use the transition property. Following is the code for creating transition effects using CSS3 −Example Live Demo .container div { width: 300px; height: 100px; background: rgb(25, 0, 255); border: 2px solid red; transition: width 2s; } .container:hover div { width: 100px; } Transition effects example Hover over the above div to reduce its width OutputThe above code will produce the following output −On hovering above the div −
To get the mean daily average count of recorded documents, use aggregate(). Within that, use $project and $group.Let us create a collection with documents −Example> db.demo451.insertOne({ ... DueDate:new ISODate("2020-03-15T10:50:35.000Z"), ... Value: 10 ... } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e7b5c5d71f552a0ebb0a6e9") } > db.demo451.insertOne({ ... DueDate:new ISODate("2020-03-14T10:50:35.000Z"), ... Value: 10 ... } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e7b5c5d71f552a0ebb0a6ea") } > db.demo451.insertOne({ ... DueDate:new ISODate("2020-03-13T10:50:35.000Z"), ... Value: 10 ... } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e7b5c5d71f552a0ebb0a6eb") }Display all documents from a collection with the help of find() ... Read More
To implement string comparison in MongoDB, use $strcasecmp. It performs case-insensitive comparison of two strings. It returns −1 if first string is “greater than” the second string.0 if the two strings are equal.-1 if the first string is “less than” the second string.Let us create a collection with documents −> db.demo490.insertOne({"Name1":"John", "Name2":"john"});{ "acknowledged" : true, "insertedId" : ObjectId("5e8496ccb0f3fa88e22790bb") } > db.demo490.insertOne({"Name1":"David", "Name2":"Bob"});{ "acknowledged" : true, "insertedId" : ObjectId("5e8496d9b0f3fa88e22790bc") } > db.demo490.insertOne({"Name1":"Carol", "Name2":"Carol"});{ "acknowledged" : true, "insertedId" : ObjectId("5e8496e5b0f3fa88e22790bd") }Display all documents from a collection with the help of find() method −> db.demo490.find();This will produce ... Read More
Use update() in MongoDB to update array object. The usage of dot notation is also required. Let us create a collection with documents −> db.demo489.insertOne( ... { ... ... ... details : [{ ... id : 101, ... "Info1" : { ... "StudentName" : "Chris" ... }, ... "Info2" : { ... "TeacherName" : "David" ... } ... }, ... { ... id : 102, ... "Info1" : ... Read More
Set the value to be deleted in a variable To delete particle data, use remove(). Let us create a collection with documents −> db.demo488.insertOne({"Name":"Chris"});{ "acknowledged" : true, "insertedId" : ObjectId("5e8351e0b0f3fa88e22790b2") } > db.demo488.insertOne({"Name":"David"});{ "acknowledged" : true, "insertedId" : ObjectId("5e8351e8b0f3fa88e22790b3") } > db.demo488.insertOne({"Name":"Bob"});{ "acknowledged" : true, "insertedId" : ObjectId("5e8351ebb0f3fa88e22790b4") } > db.demo488.insertOne({"Name":"Mike"});{ "acknowledged" : true, "insertedId" : ObjectId("5e8351eeb0f3fa88e22790b5") } > db.demo488.insertOne({"Name":"Sam"});{ "acknowledged" : true, "insertedId" : ObjectId("5e835202b0f3fa88e22790b6") } > db.demo488.insertOne({"Name":"John"});{ "acknowledged" : true, "insertedId" : ObjectId("5e835207b0f3fa88e22790b7") } > db.demo488.insertOne({"Name":"Robert"});{ "acknowledged" : true, "insertedId" : ObjectId("5e83520cb0f3fa88e22790b8") }Display all ... Read More
For a similar query to UNION two collections, use JOIN in MongoDB along with aggregate(). Let us create a collection with documents −> db.demo486.insertOne({_id:1, "Amount":30, "No":4}); { "acknowledged" : true, "insertedId" : 1 } > db.demo486.insertOne({_id:2, "Amount":40, "No":2}); { "acknowledged" : true, "insertedId" : 2 } > db.demo486.insertOne({_id:3, "Amount":60, "No":6}); { "acknowledged" : true, "insertedId" : 3 }Display all documents from a collection with the help of find() method −> db.demo486.find();This will produce the following output −{ "_id" : 1, "Amount" : 30, "No" : 4 } { "_id" : 2, "Amount" : 40, "No" : 2 } { "_id" ... Read More
The JavaScript symbol.valueOf() function returns the primitive value of a symbol object.Following is the code for implementing symbol.valueOf() function −Example Live Demo Document body { font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif; } div { font-size: 20px; font-weight: 500; } JavaScript symbol.valueOf() function CLICK HERE Click on the above button to get the value of symbols let fillEle = document.querySelector(".sample"); const symbol = Symbol('computer'); const symbol1 = Symbol(234); let res = symbol.valueOf(); let res1 = symbol1.valueOf(); document.querySelector(".Btn").addEventListener("click", () => { fillEle.innerHTML += 'res = ' + res.toString() + ""; fillEle.innerHTML += 'res1 = ' + res1.toString() + ""; }); OutputOn clicking the “CLICK HERE” button −
To check empty field in a MongoDB collection, use $exists along with $eq operator. Let us create a collection with documents −> db.demo485.insertOne({"FirstName":"Chris", "LastName":""});{ "acknowledged" : true, "insertedId" : ObjectId("5e82e9f6b0f3fa88e22790a8") } > db.demo485.insertOne({"FirstName":"David", "LastName":"Miller"});{ "acknowledged" : true, "insertedId" : ObjectId("5e82e9fdb0f3fa88e22790a9") } > db.demo485.insertOne({"FirstName":"Chris", "LastName":"Brown"});{ "acknowledged" : true, "insertedId" : ObjectId("5e82ea03b0f3fa88e22790aa") } > db.demo485.insertOne({"FirstName":"Robert", "LastName":""});{ "acknowledged" : true, "insertedId" : ObjectId("5e82ea0fb0f3fa88e22790ab") }Display all documents from a collection with the help of find() method −> db.demo485.find();This will produce the following output −{ "_id" : ObjectId("5e82e9f6b0f3fa88e22790a8"), "FirstName" : "Chris", "LastName" : "" } { "_id" ... Read More
To search array of objects, use MongoDB find().The find() method selects documents in a collection or view and returns a cursor to the selected documents..Let us create a collection with documents −> db.demo484.insertOne( ... { 'id' : 1, 'details' : [ { 'Name1' : 'Chris' }, { 'Name2' : 'David' }, { 'Name3' : 'Bob' } ] } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e82e3a4b0f3fa88e22790a1") } > db.demo484.insertOne( ... { 'id' : 1, 'details' : [ { 'Name1' : 'Chris' }, { 'Name2' : 'Carol' }, { 'Name3' : 'Bob' } ] } ... ); { ... Read More
Use db.yourCollectionName.save(yourVariableName) to set variable value, wherein “yourVariableName” is your variable.Let us see an example and create a variable −> var Info={"Name":"David", ... "CountryName":"US", ... "ProjectDetails":[{"ClientName":"David", "ProjectName":"Online Banking System"}]}Following is the query to set the variable value in the save() to save the value in the collection −> db.demo483.save(Info); WriteResult({ "nInserted" : 1 })Display all documents from a collection with the help of find() method −> db.demo483.find().pretty();This will produce the following output −{ "_id" : ObjectId("5e82e0d6b0f3fa88e22790a0"), "Name" : "David", "CountryName" : "US", "ProjectDetails" : [ { "ClientName" : "David", ... Read More