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You can use printjson() or print() to get output of MongoDB shell script. Let us create an array of objects.Following is the query to create an array of objects.> var studentDetails=[{"StudentName":"John","StudentAge":21}, {"StudentName":"Carol","StudentAge":24},{"StudentName":"David","StudentAge":25}];Following is the query to get the output of Mongo shell script using printjson() −> printjson(studentDetails);This will produce the following output −[ { "StudentName" : "John", "StudentAge" : 21 }, { "StudentName" : "Carol", "StudentAge" : 24 }, { "StudentName" : "David", "StudentAge" : 25 } ] > var studentDetails=[{"StudentName":"John","StudentAge":21}, {"StudentName":"Carol","StudentAge":24},{"StudentName":"David","StudentAge":25}];
This is a C++ program to check if a given set of three points lie on a single line or not. Three points lie on a single line if the area of the triangle formed by this points is equal to zero.The area of the triangle is −0.5 * (x1 * (y2 - y3) + x2 * (y3 - y1) + x3 * (y1 - y2)).AlgorithmsBegin Generate the points randomly. Calculate the area by using above formula. If area > 0 Then the points don't lie on the straight line. else if area ... Read More
The getTableName() method of the ResultSetMetaData (interface) retrieves and displays the name of the table which contains the given column.This method accepts an integer value representing the index of a column and, returns a String value representing the name of the table that contains the given column.To get the ResultSetMetaData object, you need to −Register the Driver: Select the required database register the Driver class of the particular database using the registerDriver() method of the DriverManager class or, the forName() method of the class named Class.DriverManager.registerDriver(new com.mysql.jdbc.Driver());Get connection: Create a connection object by passing the URL of the database, user-name and ... Read More
To pull multiple objects from an array, you can use $pull operator. Let us first create a collection with documents −> db.pullMultipleObjectsDemo.insertOne( ... { ... "ClientId" : "100", ... "ClientName" : "John", ... "ClientPersonalDetails" : [ ... { ... "ClientCountryName" : "US", ... "ClientProjectName" : "Online Book Store", ... ... }, ... { ... "ClientCountryName" : "AUS", ... ... Read More
The Euler path is a path; by which we can visit every edge exactly once. We can use the same vertices for multiple times. One graph which contains Euler Circuit is also considered in this case, as it also has the Euler path.To check whether a directed graph has Euler path or not, we have to check these conditions -There must be one single vertex an where (in-degree + 1 = out_degree)There must be one single vertex bn where (in-degree = out_degree + 1)Rest all vertices have (in-degree = out_degree) if any of these cases fails, the graph has no ... Read More
Double-buffering is the process of drawing graphics into an off-screen image buffer and then copying the contents of the buffer to the screen all at once.For the complex graphics, using double-buffering can reduce flickering issues.Java Swing automatically supports double-buffering for all of its components.Double-buffering is memory intensive, its use is only justified for components that are repainted very frequently or have particularly complex graphics to display.If a container uses double-buffering, any double-buffered children it has shared the off-screen buffer of the container, the required off-screen buffer is never larger than the on-screen size of the application.To enable double buffering, simply ... Read More
You can use $in operator to check if a value is in an array or not. Let us first create a collection with documents −> db.valueInArrayDemo.insertOne({"UserName":"John", "UserMessage":["Hi", "Hello", "Bye"]}); { "acknowledged" : true, "insertedId" : ObjectId("5cd684cf7924bb85b3f48959") } > db.valueInArrayDemo.insertOne({"UserName":"Larry", "UserMessage":["Thank You", "Amazing", "Nice"]}); { "acknowledged" : true, "insertedId" : ObjectId("5cd684d27924bb85b3f4895a") } >db.valueInArrayDemo.insertOne({"UserName":"Carol", "UserMessage":["Awesome", "Bye", "Cool"]}); { "acknowledged" : true, "insertedId" : ObjectId("5cd684d87924bb85b3f4895b") }Following is the query to display all documents from a collection with the help of find() method −> db.valueInArrayDemo.find().pretty();This will produce the following output −{ "_id" : ObjectId("5cd684cf7924bb85b3f48959"), "UserName" : "John", "UserMessage" : [ "Hi", "Hello", ... Read More
Here we will see the Bind function and the placeholders in C++. Sometimes we need to manipulate the operation of some functions as we need. We can use some default parameters to get some essence of manipulating.In C++11, one new feature is introduced, called the bind function. This helps us to do such manipulating in some easier fashion. To use these features, we have to use header file.Bind functions with the help of placeholders helps to determine the positions, and number of arguments to modify the function according to desired outputs.Placeholders are namespaces which detect the position of a ... Read More
The valueOf() method of the Enum class in java accepts a String value and returns an enum constant of the specified type.ExampleLet us create an enum with name Vehicles with 5 constants representing models of 5 different scoters with their prices as values, as shown below −enum Vehicles { //Constants with values ACTIVA125(80000), ACTIVA5G(70000), ACCESS125(75000), VESPA(90000), TVSJUPITER(75000); //Instance variable private int price; //Constructor to initialize the instance variable Vehicles(int price) { this.price = price; } ... Read More
The HTML DOM input FileUpload type property returns the value of type attribute of an element in an HTML document.SyntaxFollowing is the syntax −object.typeExampleLet us see an example of HTML DOM input file upload type property − Live Demo body{ text-align:center; background-color:#52B2CF; color:#fff; } .btn{ background-color:coral; border:none; height:2rem; border-radius:50px; width:60%; margin:1rem auto; display:block; color:#fff; outline:none; } ... Read More