ALTER TABLE ( smallinto -> boolean ) ...

I have a table with several 'smallint' fields that I'd like to convert to
booleean ... the data in each is either 0 or 1, and:

# select '1'::boolean;
bool
------
t
(1 row)
# select '0'::boolean;
bool
------
f
(1 row)

so they do cast as expected ... but, if I try to do the ALTER, I get:

# ALTER TABLE table ALTER COLUMN field1 type boolean;
ERROR: column "field1" cannot be cast to type "pg_catalog.bool"

Should this not work? If not, is there a way to do it so that it will,
without having to reload the whole table?

Thanks ...

----
Marc G. Fournier Hub.Org Networking Services (http://www.hub.org)
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