## E.296. Release 7.4.21

Release date: 2008-06-12

This release contains one serious bug fix over 7.4.20. For information about new features in the 7.4 major release, see Section E.317.

### E.296.1. Migration to Version 7.4.21

A dump/restore is not required for those running 7.4.X. However, if you are upgrading from a version earlier than 7.4.11, see Section E.306.

### E.296.2. Changes

- Make `pg_get_ruledef()` parenthesize negative constants (Tom)

  Before this fix, a negative constant in a view or rule might be dumped as, say, `-42::integer`, which is subtly incorrect: it should be `(-42)::integer` due to operator precedence rules. Usually this would make little difference, but it could interact with another recent patch to cause PostgreSQL to reject what had been a valid `SELECT DISTINCT` view query. Since this could result in pg_dump output failing to reload, it is being treated as a high-priority fix. The only released versions in which dump output is actually incorrect are 8.3.1 and 8.2.7.