What is the difference between LENGTH() and CHAR_LENGTH() functions?

Difficulty: 5/10

string functions, multibyte handling, performance

Difference Between LENGTH() and CHAR_LENGTH() in MySQL

MySQL provides both LENGTH() and CHAR_LENGTH() functions to measure string size, but they work differently depending on bytes vs characters.

1. LENGTH()

1
Returns the number of bytes in a string.
2
Useful when dealing with multi-byte character sets like UTF-8.
3
Since some characters occupy more than 1 byte, LENGTH() may return a larger value.

Example of LENGTH()

2. CHAR_LENGTH() (or CHARACTER_LENGTH())

Example of CHAR_LENGTH()

Key Difference

In summary: Use LENGTH() when storage size matters, and CHAR_LENGTH() when the number of visible characters matters.

0-2 years experience

2-5 years experience