Database - Is there a function in mysql to check the data size??

Question

What is the length() function in mysql? Isn’t it checking the number of characters:
length('Hello') //Return 7

Is there any other function that returns the number of bytes? Please help!

Answer 1

length() returns the number of bytes occupied by storage, char_length() returns the number of characters.
For example, length('Hello') should return 6 under the utf8 character set, char_length('Hello') should return 2.