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Articles by Ayyan
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What happens if the argument ‘count’ in MySQL SUBSTRING_INDEX() function has the value greater than the total number of occurrences of delimiter?
MySQL SUBSTRING_INDEX() function will return the same string as output if the argument ‘count’ has the value greater than the total number of occurrences of delimiter. It can be demonstrated with the following example −mysql> Select SUBSTRING_INDEX('My Name is Ram','a',3); +-----------------------------------------+ | SUBSTRING_INDEX('My Name is Ram','a',3) | +-----------------------------------------+ | My Name is Ram | +-----------------------------------------+ 1 row in set (0.00 sec)The above query returns the same string because 3 is greater than the total number of occurrences of delimiter provided as argument i.e. ‘a’. There are only two ‘a’ in the string.
Read MoreHow can we calculate the Date in MySQL using functions?
In MySQL, we can use the following functions to calculate the Date −CURDATE() Function − Basically it returns the current date of the computer.YEAR() Function − It returns the year of the specified date.MONTH() function − It returns the month of the specified date.DAY() Function − It returns the day of the specified date.RIGHT() Function − It returns the number of character as specified within the function from the given date. The part of the expression that compares the returns from RIGHT() function evaluates 1 or 0.To understand it, consider the data, as follows, from a table named ‘Collegedetail’ −mysql> ...
Read MoreWhich MySQL function is used to find first non-NULL value from a list of values?
We can use MySQL COALESCE() function to get the first non-NULL value as output from a list of values. In other words, this function will check all the values until non-null value found. It can take one or more than one argument. It is having the following syntax:COALESCE(value1, value2, …, valueN)ExampleFollowing is an example to demonstrate it −mysql> Select COALESCE(NULL, NULL, NULL, 'Ram', 'Aarav', NULL); +--------------------------------------------------+ | COALESCE(NULL, NULL, NULL, 'Ram', 'Aarav', NULL) | +--------------------------------------------------+ | Ram | +--------------------------------------------------+ 1 row in set (0.00 sec)
Read MoreWhat MySQL returns if we use NULL, as both the arguments, as one of the argument and as a separator, in CONCAT_WS() function?
NULL as both argumentsMySQL returns blank output if we will use NULL as both of the arguments in CONCAT_WS() function.Examplemysql> Select CONCAT_WS('', NULL, NULL); +-------------------------+ | CONCAT_WS('', NULL, NULL) | +-------------------------+ | | +-------------------------+ 1 row in set (0.00 sec)NULL as one of the argumentMySQL returns the value of the other argument as output if we will use NULL as one of the argument in CONCAT_WS() function.Examplemysql> Select CONCAT_WS('', NULL, 'Delhi'); +----------------------------+ | CONCAT_WS('', NULL, 'Delhi') | +----------------------------+ | Delhi ...
Read MoreHow can we fetch a particular row as output from a MySQL table?
For fetching a particular row as output, we need to use WHERE clause in the SELECT statement. It is because MySQL returns the row based on the condition parameter given by us after WHERE clause.ExampleSuppose we want to fetch a row which contains the name ‘Aarav’ from student table then it can be done with the help of the following query −mysql> Select * from Student WHERE Name = 'Aarav'; +------+-------+---------+---------+ | Id | Name | Address | Subject | +------+-------+---------+---------+ | 2 | Aarav | Mumbai | History | +------+-------+---------+---------+ 1 row in set (0.00 sec)
Read MoreHow to convert a Boolean to Integer in JavaScript?
Yes, it is possible to convert Boolean to Integer in JavaScript, using the Ternary Operator. Example You can try to run the following code to convert Boolean to Integer − JavaScript Boolean var answer = true; document.write(answer); var pass_marks = answer ? 90 : 40; document.write("Passing Marks: "+pass_marks);
Read MoreWhat are async generator methods in JavaScript?
Async generator functions are the same like generator function. The async generator functions will return an object, whereas an async generator whose methods such as next, throw and return promises for { value, done }, instead returning directly.ExampleHere’s an example from GitHub showing function returning async generator object −async function* readLines(path) { let file = await fileOpen(path); try { while (!file.EOF) { yield await file.readLine(); } } finally { await file.close(); } }
Read MoreIs it a good practice to place all declarations at the top in JavaScript?
Yes, it is a good practice to place all the JavaScript declarations at the top. Let’s see an example −Example JavaScript String match() Method // all the variables declared at top var str, re, found; str = "For more information, see Chapter 3.4.5.1"; re = /(chapter \d+(\.\d)*)/i; found = str.match( re ); document.write(found ); The following are the valid reasons −Gives a single place to check for all the variables.Helps in avoiding global variablesRe-declarations are avoided.The code is easy to read for others as well.
Read MoreHow to write "Hello World" Program in C++?
To run the hello world program, you'll have to follow the following steps −Write a C++ programNow that you have a compiler installed, its time to write a C++ program. Let's start with the epitome of programming example's, it, the Hello world program. We'll print hello world to the screen using C++ in this example. Create a new file called hello.cpp and write the following code to it −#include int main() { std::cout
Read MoreWhat is the Java Runtime Environment (JRE)?
JRE is Java Runtime Environment and is the machine-specific implementation of JVM. It contains libraries like rt.jar, class loaders etc which are used by JVM.
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