The following bug has been logged online:

Bug reference: 1933
Logged by: Duncan Crombie
Email address: duncan (AT) chirp (DOT) com.au
PostgreSQL version: 8.0.1
Operating system: Darwin (OSX)
Description: ADD COLUMN with DEFAULT resets table oids
Details:

The following command causes all oids in the affected table to be reset to
new values:

ALTER TABLE items ADD COLUMN publish bool DEFAULT true;

The following causes no problems:

ALTER TABLE items ADD COLUMN publish bool;
ALTER TABLE items ALTER publish SET DEFAULT true;

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TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match

"Duncan Crombie" <duncan (AT) chirp (DOT) com.au> writes:
Yup, that's an oversight. Fix committed, will appear in 8.0.4.
Thanks for the report!

regards, tom lane

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