Message-ID: <46C349EA.5050201@etelos.com>
Date: Wed, 15 Aug 2007 11:46:02 -0700
From: Jon Collette <jon@etelos.com>
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To: pgsql-sql@postgresql.org
Subject: Boolean without default declared
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If a column with a boolean datatype doesn't have a default value.  What 
type of value is set if nothing is inserted into that column?  Here is 
my test table and the queries I have tried.  I can't seem to be able to 
select the rows where happy has no value.

            Table "public.users"
 Column |         Type          | Modifiers
--------+-----------------------+-----------
 id     | character varying(32) |
 email  | text                  |
 happy  | boolean               |
 money  | numeric               |


*select * from users;                *
 id | email  | happy |  money 
----+--------+-------+---------
 4  | me     |       | 1324.23
 4  | me     |       | 1324.23
 3  | as     |       |   123.2
 1  | afjssd | t     |       

*select * from users where happy;*
 id | email  | happy | money
----+--------+-------+-------
 1  | afjssd | t     |     

*select * from users where not happy;*
 id | email | happy | money
----+-------+-------+-------
(0 rows)

*select * from users where happy = NULL;*
 id | email | happy | money
----+-------+-------+-------
(0 rows)

*select * from users where happy = '';*
ERROR:  invalid input syntax for type boolean: ""