What is the difference between LENGTH() and CHAR_LENGTH() functions?
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()
Returns the number of bytes in a string.
Useful when dealing with multi-byte character sets like UTF-8.
Since some characters occupy more than 1 byte, LENGTH() may return a larger value.
Example of LENGTH()
2. CHAR_LENGTH() (or CHARACTER_LENGTH())
Returns the number of characters in a string.
Counts logical characters, regardless of how many bytes each uses.
Useful when validating input lengths for multilingual text.
Example of CHAR_LENGTH()
Key Difference
**LENGTH() → counts bytes
CHAR_LENGTH() → counts characters
In summary: Use LENGTH() when storage size matters, and CHAR_LENGTH() when the number of visible characters matters.