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George John has Published 1081 Articles

George John
4K+ Views
A Binary Heap is a complete binary tree which is either Min Heap or Max Heap. In a Max Binary Heap, the key at root must be maximum among all keys present in Binary Heap. This property must be recursively true for all nodes in that Binary Tree. Min Binary ... Read More

George John
126 Views
You can use buidInfo along with runCommand to check MongoDB for 32 bits or 64 bits. First switch your database to admin. Following is the syntaxuse adminAfter that use the following syntax to know if my server runs MongoDB 64 bits or notdb.runCommand(buildInfo)Now execute the above syntax> use admin switched ... Read More

George John
5K+ Views
You can use CASE statement to count two different columns in a single query. To understand the concept, let us first create a table. The query to create a table is as follows.mysql> create table CountDifferentDemo - > ( - > ProductId int NOT NULL AUTO_INCREMENT PRIMARY KEY, ... Read More

George John
124 Views
The empty() method of the LongStream class in Java returns an empty sequential LongStream.The syntax is as follows.static LongStream empty()To use the LongStream class in Java, import the following package.import java.util.stream.LongStream;The following is an example to implement LongStream empty() method in Java.Example Live Demoimport java.util.stream.LongStream; public class GFG { public ... Read More

George John
2K+ Views
Yes, it is possible to rename using aggregation. Let us first create a collection with documents> db.renameIdDemo.insertOne({"StudentName":"Chris"}); { "acknowledged" : true, "insertedId" : ObjectId("5c9a1760353decbc2fc927c5") } > db.renameIdDemo.insertOne({"StudentName":"Robert"}); { "acknowledged" : true, "insertedId" : ObjectId("5c9a1765353decbc2fc927c6") } > db.renameIdDemo.insertOne({"StudentName":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5c9a176b353decbc2fc927c7") ... Read More

George John
170 Views
You can use two approaches to know the version of MySQL. In the first approach, you can use version() to know the MySQL Server version. The first approach is as followsSELECT VERSION();In the second approach, you can use SHOW VARIABLES command to know the MySQL version. The second approach is ... Read More

George John
2K+ Views
In this section we will see how to perform sorting algorithm in C++. A sorted array is an array in which each of the elements are sorted in some order such as numerical, alphabetical etc. There are many algorithms to sort a numerical array such as bubble sort, insertion sort, ... Read More

George John
144 Views
The difference between toArray() and toArray(T[] arr) in Java AbstractCollection is that both the methods returns an array containing all of the elements in this collection, but the latter has some additional features i.e. the runtime type of the returned array is that of the specified array.The syntax is as ... Read More

George John
176 Views
To increment a value inside a nested array, use positional operator ($). Let us first create a collection with documents> db.incrementInNestedArrayDemo.insertOne( ... { ... "StudentId":100, ... "ProjectDetails": ... [ ... {"ProjectId":567778888, ... "TeamSize":4 ... }, ... ... Read More

George John
1K+ Views
The best way to change the date format in MySQL SELECT is as followsSELECT DATE_FORMAT(yourColumnName, "%d/%m/%Y %H:%i") AS anyAliasName FROM yourTableName WHERE yourCondition;To understand the above concept, let us create a table. The query to create a table is as followsmysql> create table bestDateFormatDemo - > ( ... Read More