This articles covers how to encode and decode JSON objects using Java programming language. Let's start with preparing the environment to start our programming with Java for JSON.EnvironmentBefore you start with encoding and decoding JSON using Java, you need to install any of the JSON modules available. For this tutorial ... Read More

Subqueries can work well in a SELECT statement FROM clause. Following is the syntax for the same −SELECT … FROM(subquery) [AS] name …To make it understand we are using the following data from table ‘cars’ −mysql> Select * from Cars; +------+--------------+---------+ | ID   | Name         ... Read More

By default, the bit values assigned to the user variables are binary strings. It can be illustrated by assigning the bit value to a user variable and then by retrieving them as follows −mysql> SET @abc = 0b1000011; Query OK, 0 rows affected (0.00 sec) mysql> Select @abc; +------+ ... Read More

This example shows how to search the minimum and maximum element in an array by using Collection.max() and Collection.min() methods of Collection class.Exampleimport java.util.Arrays; import java.util.Collections; public class Main {    public static void main(String[] args) {       Integer[] numbers = { 8, 2, 7, 1, ... Read More

Following are the notable differences between HashMap and ConcurrentHashMap classes in Java. HashMapConcurrentHashMapSynchronizedHashMap is not synchronized.ConcurrentHashMap is synchronized.Thread SafeHashMap is not thread safe.ConcurrentHashMap is thread safe.Iterator typeHashMap iterator is fail-fast and ArrayList throws ConcurrentModificationException if concurrent modification happens during iteration.ConcurrentHashMap is fail-safe and it will never throw ConcurrentModificationException during iteration.Null valuesHashMap ... Read More

When we use RAND() function along with both ORDER BY and LIMIT clause in a query, MySQL returns the different set of rows or values each time. To understand it considers a table ‘Employee’ having the following records −mysql> Select * from Employee; +----+--------+--------+ | ID | Name   | ... Read More

MySQL REVERSE() function make it possible to invert a string. Its syntax is as follows −SyntaxREVERSE(STR)Here, STR is a string which we want to invert.Examplemysql> Select REVERSE('MySQL'); +------------------+ | REVERSE('MySQL') | +------------------+ | LQSyM            | +------------------+ 1 row in set (0.05 sec)

When we use FIND_IN_SET() function in WHERE clause then it searches the search string within the given string as specified in the argument and retrieves all the columns from concerned rows. Following is an example to demonstrate it −ExampleIn this example, we are getting the columns from ‘Student’ table where ... Read More

Both the functions are string functions and return the number of characters present in the string. But they differ in the concept that CHAR_LENGTH() function measures the string length in ‘characters’ whereas LENGTH() function measures the string length in ‘bytes’. In other words, we can say that CHAR_LENGTH() function is ... Read More

Followings are the ways in which we can write a query that returns only records that matches multiple conditions on the same columnBy using ‘OR’ logical operatorAs we know that MySQL ‘OR’ operator compares two expressions and returns TRUE if either of the expression is TRUE. Following example demonstrate that ... Read More