Byte or Character Length semantics?

When defining a CHAR/VARCHAR database column or program variable, you must specify a size. When using a multibyte character set, the unit of this size matters: it can be specified in bytes or characters. In programs, the size unit of CHAR/VARCHAR variables depends on the length semantics defined by the FGL_LENGTH_SEMANTICS environment variable. In databases, the size unit of the CHAR/VARCHAR columns can be expressed in bytes or characters, depending on the database server and its configuration.