Appending to an array - Mailing list pgsql-general

All,

    I've got a tablewhere one of the columns contains an array.  What I'm
trying to do is to append or insert into the array.  I know I can so
something like..
    UPDATE mytable set myarray[10] = 'some value' WHERE...

..to change a particular array element, and this be used to extend the
array if the array is not that size yet, but what I need to figure out is
how to do that when I don't know the size of the array at any given time.

Thanks

Jay