Log Message:
-----------
Update discussion of ALTER TABLE ADD COLUMN, per Michael Fuhr.
Modified Files:
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pgsql/doc/src/sgml:
ddl.sgml (r1.36 -> r1.37)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ddl.sgml.diff?r1=1.36&r2=1.37)