Chapter 03 Using Single-Row Functions

Question 1

What is CONCAT(c1,c2), and how does it work?

Answer 1

CONCAT(c1,c2) takes two arguments, where c1 and c2 are both character strings. This function
returns c2 appended to c1. If c1 is NULL, then c2 is returned. If c2 is NULL, then c1 is returned. If both c1 and c2 are NULL, then NULL is returned. CONCAT returns the same results as using the concatenation operator: c1||c2.