mysql comments require a space after the '--' before text

<blockquote>
From a “-- ” sequence to the end of the line. In MySQL, the “-- ” (double-dash) comment style requires the second dash to be followed by at least one whitespace or control character (such as a space, tab, newline, and so on).
</blockquote>


from https://dev.mysql.com/doc/refman/5.1/en/comments.html