adding a COLUMN with SQL ALTER TABLE, or CHGPF command

I have never used the SQL ALTER TABLE statement to add a column to a
physical files, nor have I used the CHGPF command, or the CHGPFM
command.

Just wanted to tell you that I am really benefiting from the
midrange.com archives on this topic, (Mark Waterbury and Eric DeLong),
as recently as February 2008.
My Google search found some informative links to www.ibmsystemsmag.com
and at www-1.ibm.com/support.

IBM tech support promptly answered my main questions about ALTER TABLE
(shown below)
<IBM help>

You can use the CHGPF FILE(library/file) SRCFILE(srclib/srcfile)
SRCMBR(srcmbr)
CL command and specify new DDS source for a file. For example if you
are simply wanting to add a new field, you would create the DDS source
identical to the original but simply add a new field. You then specify
this source file member on the CHGPF to change the file. The data will
be preserved and simply have the new field added. As long as you do not
change any of the names/attributes of the other existing fields, the
data will be preserved.

The other method is to use SQL - The ALTER TABLE function.
You can add a field to a file using this method quite easily.

Both the above 2 methods will automatically copy the data from the
original file to the new file.

Hope this is helpful, let me know if you have any other questions, or
if I can go ahead and close out the pmr for you at this time.
</IBM help>