Syntax:
IS_IPV4_COMPAT(expr)

This function takes an IPv6 address represented in numeric form as a
binary string, as returned by INET6_ATON(). It returns 1 if the
argument is a valid IPv4-compatible IPv6 address, 0 otherwise (unless
expr is NULL, in which case the function returns NULL). IPv4-compatible
addresses have the form ::ipv4_address.

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

