How to "concat" row values into a single column?

Arg.  I know I've seen this before and I may have actually done it
before, but I'll be darned if I can remember how.

In 9.2, I have two tables kinda like these:

CREATE TABLE ALARM_TYPE
(
  AT_ID           NUMBER                        NOT NULL,
  ALARM_INTERVAL  NUMBER                        NOT NULL
)
/

Insert into ALARM_TYPE
   (AT_ID, ALARM_INTERVAL)
 Values
   (1, 10);
COMMIT;

CREATE TABLE CONTACT
(
  CONTACT_ID           NUMBER                   NOT NULL,
  AT_ID                NUMBER                   NOT NULL,
  EMAIL_ADDRESS        VARCHAR2(200)            NOT NULL
)
/

Insert into CONTACT
   (CONTACT_ID, AT_ID, EMAIL_ADDRESS)
 Values
   (3, 1, 'someone@xxxxxxxxxx');
Insert into CONTACT
   (CONTACT_ID, AT_ID, EMAIL_ADDRESS)
 Values
   (4, 1, 'else@xxxxxxxxxx');
COMMIT;

I would like a query to return a single row:

1       10      someone@xxxxxxxxxx, else@xxxxxxxxxx

I had tried fudging SYS_CONNECT_BY_PATH and some of the XML functions,
but I'm not having any luck.  Something along those lines would be an
ideal solution for me for this project.  But since these are new tables,
I'm not opposed to a structure change, although I'm not sure I want to
go with the OO approach (e.g. VARRAY column for the email addresses).

Of course, this is way-oversimplified for the sake of brevity.

Anyone???

TIA!
Rich
--
http://www.freelists.org/webpage/oracle-l


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