Count Unique Values in a MySQL Column

Ankitha Reddy
Updated on 30-Jul-2019 22:30:21

304 Views

By using DISTINCT keyword along with column name as the argument of COUNT() function we can count the number of unique values in a column. The syntax is as follows − SELECT COUNT(DISTINCT Col_name) FROM table_name; Example Suppose we have the following table mysql> Select * from tender; +----------+--------------+--------------+-------+ | clientid | client_Fname | Client_Lname | value | +----------+--------------+--------------+-------+ | 100 | Mohan | Kumar | 60000 | | 101 | Sohan ... Read More

What Does the toString() Method Do in Java?

Sai Subramanyam
Updated on 30-Jul-2019 22:30:21

170 Views

The toString(Object[] a) method of the java.util.Arrays class returns a string representation of the contents of the specified Object array. If the array contains other arrays of elements, they are converted to strings by the Object.toString() method inherited from Object, which describes their identities rather than their contents. Example import java.util.Arrays; public class ArrayDemo { public static void main(String[] args) { Object[] ob1 = new Object[] { 10, 20 }; System.out.println("The array is:"); for (Object number ... Read More

Set Java Path in Linux OS

Manikanth Mani
Updated on 30-Jul-2019 22:30:21

458 Views

Environment variable PATH should be set to point to where the Java binaries have been installed. Refer to your shell documentation if you have trouble doing this.Example, if you use bash as your shell, then you would add the following line to the end of your '.bashrc: export PATH=/path/to/java:$PATH'

Set Java Path in Mac OS

Anjana
Updated on 30-Jul-2019 22:30:21

1K+ Views

Environment variable PATH should be set to point to where the Java binaries have been installed. Refer to your shell documentation if you have trouble doing this.Example, if you use bash as your shell, then you would add the following line to the end of your '.bashrc: export PATH=/path/to/java:$PATH'

Difference between C++ String Constants and Character Constants

karthikeya Boyini
Updated on 30-Jul-2019 22:30:21

877 Views

In C++, a character in single quotes is a character literal. It's of type char. For example, 'a' is of type char with a value 97 on an ASCII based system.A character or a string of characters together in double quotes represent a string literal. It's of type const char[] and refers to an array of size length of string + 1. That extra character is there for marking the string's ending.String literals can be arbitrarily long, such as "abcdefg". Character literals almost always contain just a single character. When these are being printed, string literals are printed till the ... Read More

MySQL SUM Function with NULL Values

George John
Updated on 30-Jul-2019 22:30:21

1K+ Views

Suppose if we are calculating the sum of the values of a column which also have NULL values then MySQL SUM() function ignores the NULL values and does the sum of the rest of the values. To understand it, consider the following example of table ‘employee’, having following details − mysql> Select * from Employee; +----+--------+--------+ | ID | Name | Salary | +----+--------+--------+ | 1 | Gaurav | 50000 | | 2 | Rahul | 20000 | | 3 | Advik | 25000 | | 4 | ... Read More

Types of Array in Java

varun
Updated on 30-Jul-2019 22:30:21

373 Views

Java supports single dimensional and multidimensional arrays. See the example below:Example Live Demopublic class Tester {    public static void main(String[] args) {       double[] myList = {1.9, 2.9, 3.4, 3.5};       // Print all the array elements       for (double element: myList) {          System.out.print(element + " ");       }       System.out.println();       int[][] multidimensionalArray = { {1,2},{2,3}, {3,4} };       for(int i = 0 ; i < 3 ; i++) {          //row          for(int j = 0 ; j < 2; j++) {             System.out.print(multidimensionalArray[i][j] + " ");          }          System.out.println();       }    } }Output1.9 2.9 3.4 3.5 1 2 2 3 3 4

Set JAVA_HOME for Java in Linux

Ayyan
Updated on 30-Jul-2019 22:30:21

281 Views

Assuming you have installed Java in \usr\local\java\jdk directory −if you use bash as your shell, then you would add the following line to the end of your '.bashrc: export JAVA_HOME=\usr\local\java\jdk'

Search Data from MySQL Table Based on Similar Sound Values

Sai Subramanyam
Updated on 30-Jul-2019 22:30:21

141 Views

With the help of SOUNDS LIKE operator, MySQL search the similar sound values from the table. Syntax Expression1 SOUNDS LIKE Expression2 Here, both Expression1 and Expression2 will be compared based on their English pronunciation of sound. Example Following is an example from ‘student’ table which will match the two expressions based on the pronunciation of sound mysql> Select Id, Name, Address, Subject from student where name sounds like 'hrst'; +------+---------+---------+----------+ | Id | Name | Address | Subject | +------+---------+---------+----------+ | 15 | Harshit | Delhi | Commerce | +------+---------+---------+----------+ 1 row in set (0.00 sec)

Set JAVA_HOME for Java in Mac OS

Manikanth Mani
Updated on 30-Jul-2019 22:30:21

746 Views

Assuming you have installed Java in \usr\local\java\jdk directory −if you use bash as your shell, then you would add the following line to the end of your '.bashrc: export JAVA_HOME=\usr\local\java\jdk'

Advertisements