Articles on Trending Technologies

Technical articles with clear explanations and examples

What are the different ways of copying an array into another array in Java?

Maruthi Krishna
Maruthi Krishna
Updated on 02-Jul-2020 906 Views

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

Count occurrences of known distinct values in MySQL

AmitDiwan
AmitDiwan
Updated on 02-Jul-2020 257 Views

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

What happens if try to access an element with an index greater than the size of the array in Java?

Maruthi Krishna
Maruthi Krishna
Updated on 02-Jul-2020 3K+ Views

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 elements ...

Read More

Can you pass the negative number as an Array size in Java?

Maruthi Krishna
Maruthi Krishna
Updated on 02-Jul-2020 3K+ Views

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];While creating array in this way, you must ...

Read More

Can you assign an Array of 100 elements to an array of 10 elements in Java?

Maruthi Krishna
Maruthi Krishna
Updated on 02-Jul-2020 3K+ Views

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];While creating array in this way, you must specify ...

Read More

What are the best practices to keep in mind while using packages in Java?

Maruthi Krishna
Maruthi Krishna
Updated on 02-Jul-2020 1K+ Views

You can create the .class files of all the Java classes and interfaces related to each other in one folder automatically by declaring them under same package. A package is nothing but a directory storing classes and interfaces of a particular concept.Creating a packageYou can create a package and add required classes/interfaces in it just by declaring the package on the top of the Class/Interface files using the keyword package as −Package package_name;ExampleFollowing Java program, demonstrates the declaration of a package in Java.package com.tutorialspoint.mypackage; public class Sample{    public void demo(){       System.out.println("This is a method of the ...

Read More

How can I display all databases in MySQL and for each database show all tables?

AmitDiwan
AmitDiwan
Updated on 02-Jul-2020 593 Views

For this, you can use INFORMATION_SCHEMA. Following is the syntax −select my_schema.SCHEMA_NAME, group_concat(tbl.TABLE_NAME) from information_schema.SCHEMATA my_schema left join information_schema.TABLES tbl on my_schema.SCHEMA_NAME=tbl.TABLE_SCHEMA group by my_schema.SCHEMA_NAME;Let us implement the above syntax in order to show all databases in MySQL and for each database −mysql> select my_schema.SCHEMA_NAME, group_concat(tbl.TABLE_NAME)    from information_schema.SCHEMATA my_schema    left join information_schema.TABLES tbl on my_schema.SCHEMA_NAME=tbl.TABLE_SCHEMA group by my_schema.SCHEMA_NAME;This will produce the following output −+---------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | SCHEMA_NAME               | group_concat(tbl.TABLE_NAME)                                               ...

Read More

Difference between import and package in Java?

Maruthi Krishna
Maruthi Krishna
Updated on 02-Jul-2020 3K+ Views

In Java classes and interfaces related to each other are grouped under a package. Package is nothing but a directory storing classes and interfaces of a particular concept. For example, all the classes and interfaces related to input and output operations are stored in java.io package.Creating a packageYou can group required classes and interfaces under one package just by declaring the package at the top of the Class/Interface (file) using the keyword package as −package com.tutorialspoint.mypackage; public class Sample{    public void demo(){       System.out.println("This is a method of the sample class");    }    public static void main(String ...

Read More

How do you print the content of an array in Java?

Maruthi Krishna
Maruthi Krishna
Updated on 02-Jul-2020 627 Views

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

Comma separated argument applicable for IN operator in MySQL?

AmitDiwan
AmitDiwan
Updated on 02-Jul-2020 287 Views

Use FIND_IN_SET() for command separated argument. Let us first create a table −mysql> create table DemoTable604 (Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, Title varchar(100)); Query OK, 0 rows affected (0.51 sec)Insert some records in the table using insert command −mysql> insert into DemoTable604(Title) values('MySQL'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable604(Title) values('C++'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable604(Title) values('MongoDB'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable604(Title) values('Java'); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> select *from DemoTable604;This ...

Read More
Showing 52461–52470 of 61,297 articles
Advertisements