How can we combine functions in MySQL?

Combining of functions in MySQL is quite possible by providing a function as the argument of other function. It is also called nesting of functions. To understand it, consider some examples below

mysql> Select UPPER(CONCAT('www.','tutorialspoint','.com'))As Tutorials;
+------------------------+
| Tutorials              |
+------------------------+
| WWW.TUTORIALSPOINT.COM |
+------------------------+
1 row in set (0.00 sec)

mysql> Select LOWER(CONCAT('WWW.','TUTORIALSPOINT','.COM'))As Tutorials;
+------------------------+
| Tutorials              |
+------------------------+
| www.tutorialspoint.com |
+------------------------+
1 row in set (0.00 sec)

The above queries combine UPPER() and LOWER() function with CONCAT() function.

Similarly, we can combine more functions with each other; eve more than two functions can also be combined.