If you have an SMTP service running, you can outfile to the drop directory. If you have high volume, you may result with duplicate file names, but there are ways to avoid that.
Otherwise, you will need to create a UDF.
Here's a sample trigger solution:
CREATE TRIGGER test.autosendfromdrop BEFORE INSERT ON test.emaildrop
FOR EACH ROW BEGIN
/* START THE WRITING OF THE EMAIL FILE HERE*/
SELECT concat("To: ",NEW.To),
concat("From: ",NEW.From),
concat("Subject: ",NEW.Subject),
NEW.Body
INTO OUTFILE
"C:\\inetpub\\mailroot\\pickup\\mail.txt"
FIELDS TERMINATED by '\r\n' ESCAPED BY '';
END;
To markup the message body you will need something like this...
CREATE FUNCTION `HTMLBody`(Msg varchar(8192))
RETURNS varchar(17408) CHARSET latin1 DETERMINISTIC
BEGIN
declare tmpMsg varchar(17408);
set tmpMsg = cast(concat(
'Date: ',date_format(NOW(),'%e %b %Y %H:%i:%S -0600'),'\r\n',
'MIME-Version: 1.0','\r\n',
'Content-Type: multipart/alternative;','\r\n',
' boundary=\"----=_NextPart_000_0000_01CA4B3F.8C263EE0\"','\r\n',
'Content-Class: urn:content-classes:message','\r\n',
'Importance: normal','\r\n',
'Priority: normal','\r\n','','\r\n','','\r\n',
'This is a multi-part message in MIME format.','\r\n','','\r\n',
'------=_NextPart_000_0000_01CA4B3F.8C263EE0','\r\n',
'Content-Type: text/plain;','\r\n',
' charset=\"iso-8859-1\"','\r\n',
'Content-Transfer-Encoding: 7bit','\r\n','','\r\n','','\r\n',
Msg,
'\r\n','','\r\n','','\r\n',
'------=_NextPart_000_0000_01CA4B3F.8C263EE0','\r\n',
'Content-Type: text/html','\r\n',
'Content-Transfer-Encoding: 7bit','\r\n','','\r\n',
Msg,
'\r\n','------=_NextPart_000_0000_01CA4B3F.8C263EE0--'
) as char);
RETURN tmpMsg;
END ;