Syntax:
MD5(str)

Calculates an MD5 128-bit checksum for the string. The value is
returned as a string of 32 hexadecimal digits, or NULL if the argument
was NULL. The return value can, for example, be used as a hash key. See
the notes at the beginning of this section about storing hash values
efficiently.

The return value is a string in the connection character set.

If FIPS mode is enabled, MD5() returns NULL. See
https://dev.mysql.com/doc/refman/8.0/en/fips-mode.html.

URL: https://dev.mysql.com/doc/refman/8.0/en/encryption-functions.html

