Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Array is a container which can hold a fix number of items and these items should be of the same type. Most of the data structures make use of arrays to implement their algorithms. Following are the important terms to understand the concept of Array.Element: Each item stored in an array is called an element.Index: Each location of an element in an array has a numerical index, which is used to identify the element.Storing Objects in an arrayYes, since objects are also considered as datatypes (reference) in Java, you can create an array of the type of a particular class ... Read More
An array is a data structure/container/object that stores a fixed-size sequential collection of elements of the same type. The size/length of the array is determined at the time of creation.The position of the elements in the array is called as index or subscript. The first element of the array is stored at the index 0 and, the second element is at the index 1 and so on.Each element in an array is accessed using an expression which contains the name of the array followed by the index of the required element in square brackets.For example, if an array of 6 ... Read More
An array is a data structure/container/objectthat stores a fixed-size sequential collection of elements of the same type. The size/length of the array is determined at the time of creation.The position of the elements in the array is called as index or subscript. The first element of the array is stored at the index 0 and, the second element is at the index 1 and so on.Each element in an array is accessed using an expression which contains the name of the array followed by the index of the required element in square brackets.For example, if an array of 6 elements ... Read More
A collection object in Java is the one which stores references of other objects in it. The java.util package provides the classes and interfaces for collections. There are four main collection interfaces namely Set Lists, Queues, Maps.Set − The set object is a collection which stores group of elements, it grows dynamically and it does not allow duplicate elements.HashSet and LinkedHashSet are the classes that implements Set interface. You can create a Set object by implementing either of these classes.Exampleimport java.util.HashSet; public class SetExample { public static void main(String args[]) { //Instantiating the HashSet ... Read More
In Java, serialization is a concept using which we can write the state of an object into a byte stream so that we can transfer it over the network (using technologies like JPA and RMI).To serialize an object −Make sure the class implements the Serializable interface.Create a FileOutputStream object representing the file (abstract path) of the file to which the object is to be stored.Create a ObjectOutputStream object by passing the above created FileOutputStream object.Write the object to the file using the writeObject() method.To de-serialize an objectCreate a FileInputStream object representing the file that contains the serialized object.Read the object ... Read More
For negative values, use reverse() along with concat(). Let us first create a table −mysql> create table DemoTable632 ( histogramId int NOT NULL AUTO_INCREMENT PRIMARY KEY, histogramValue int, histogramImage text ); Query OK, 0 rows affected (0.78 sec)Insert some records in the table using insert command −mysql> insert into DemoTable632(histogramValue) values(2); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable632(histogramValue) values(3); Query OK, 1 row affected (0.34 sec) mysql> insert into DemoTable632(histogramValue) values(-6); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable632(histogramValue) values(-5); Query OK, 1 row affected (0.13 sec)Display all records from the table ... Read More
In general, arrays are the containers that store multiple variables of the same datatype. These are of fixed size and the size is determined at the time of creation. Each element in an array is positioned by a number starting from 0.You can access the elements of an array using name and position as −System.out.println(myArray[3]); //Which is 1457Creating an array in JavaIn Java, arrays are treated as referenced types you can create an array using the new keyword similar to objects and populate it using the indices as −int myArray[] = new int[7]; myArray[0] = 1254; myArray[1] = 1458; myArray[2] ... Read More
In general, arrays are the containers that store multiple variables of the same datatype. These are of fixed size and the size is determined at the time of creation. Each element in an array is positioned by a number starting from 0. You can access the elements of an array using name and position as −System.out.println(myArray[3]); //Which is 1457 Creating an array in Java:In Java, arrays are treated as referenced types you can create an array using the new keyword similar to objects and populate it using the indices as −int myArray[] = new int[7]; myArray[0] = 1254; myArray[1] = ... Read More
For this, you can use aggregate function SUM(). Let us first create a table −mysql> create table DemoTable636 ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentFirstName varchar(100) ); Query OK, 0 rows affected (0.51 sec)Insert some records in the table using insert command −mysql> insert into DemoTable636(StudentFirstName) values('John'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable636(StudentFirstName) values('Robert'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable636(StudentFirstName) values('Robert'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable636(StudentFirstName) values('Sam'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable636(StudentFirstName) values('Mike'); Query OK, ... Read More
Let us first create a table −mysql> create table DemoTable638 (Name varchar(100), Marks int); Query OK, 0 rows affected (0.68 sec)Insert some records in the table using insert command −mysql> insert into DemoTable638 values('John', 67); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable638 values('John', 90); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable638 values('David', 99); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable638 values('John', 60); Query OK, 1 row affected (0.13 sec)Display all records from the table using select statement −mysql> select *from DemoTable638;This will produce the following output −+-------+-------+ | ... Read More