Re: alter column type

CAUTION: This is very dangerous and may cause corruption.
         *** DO THIS IN A TEST DATABASE FIRST ***
 
--1. Get the oid for int8 (bigint)
SELECT t.oid
  FROM pg_type t
WHERE typname = 'int8';

--2. Get the oid for your table
SELECT c.oid,
       c.relname as table,
       a.attname ,
       a.atttypid,
       a.*
  FROM pg_class c
  JOIN pg_namespace n ON (n.oid = c.relnamespace)
  JOIN pg_attribute a ON ( a.attrelid = c.oid )
 WHERE c.relname = 'dogs'
   AND n.nspname = 'public'
   AND a.attname = 'good_watchdog'
   AND NOT attisdropped;

BEGIN;

UPDATE pg_attribute a
   SET atttypid = <t.oid from 1>
 WHERE a.attrelid = <c.oid from 2>
   AND attname = <your column to change>;

COMMIT;