ALTER CONVERSION name RENAME TO newname
ALTER CONVERSION name OWNER TO newowner

name

The name (optionally schema-qualified) of an existing conversion.

newname

The new name of the conversion.

newowner

The new owner of the conversion. To change the owner of a conversion, you must be a superuser.

ALTER CONVERSION iso_8859_1_to_utf_8 RENAME TO latin1_to_unicode;

ALTER CONVERSION iso_8859_1_to_utf_8 OWNER TO joe;