PostgreSQL:

ALTER CONVERSION

Topic

ALTER CONVERSION changes the definition of a conversion.

You must own the conversion to use ALTER CONVERSION. To alter the owner, you must also be a direct or indirect member of the new owning role, and that role must have CREATE privilege on the conversion's schema. (These restrictions enforce that altering the owner doesn't do anything you couldn't do by dropping and recreating the conversion. However, a superuser can alter ownership of any conversion anyway.)

Example

ALTER CONVERSION name RENAME TO new_name
ALTER CONVERSION name OWNER TO new_owner
ALTER CONVERSION name SET SCHEMA new_schema