The SIZEOF (or VSIZE) function calculates the maximum length,
    in octets, of a value expression of any data type. It returns
    the length or storage width of the value expression. Like OCTET_
    LENGTH, SIZEOF returns the number of eight-bit units (octets)
    rather than the number of characters if the expression yields a
    text string in a multi-byte character set. You can use VSIZE as
    an alternative for SIZEOF.