Re: Odd behavior with NULL value

I think that this page will explain it all:
http://www.postgresql.org/idocs/index.php?functions-comparison.html

|On 011220 17:05
|Bob Smith, Hammett & Edison, Inc. (bsmith@h-e.com) wrote the following...
|
|See example below of using NULL values with type DATE.  It behaves
|strangely in expressions, "(x <> null)" gives an entirely different
|result than "not(x = null)".  Is this intended behavior, if so, why?
|If not, is this a bug?
|
|On a related note, does anyone know if 'current' works with DATE?  With
|TIMESTAMP it always evaluates to the time as of the retrieval of the
|value, not as of the insertion, but for DATE it looks like it gets
|evaluated at insertion (I can't tell for sure from my test db for another
|8 hours or so, I could just roll the date forward on the server, but I'd
|like to keep my job...)
|
|Thanks to anyone who can shed some light on this!
|
|rsj=> \d test
|          Table "test"
| Attribute |  Type   | Modifier
|-----------+---------+----------
| key       | integer |
| date      | date    |
|
|rsj=> select * from test;
| key |    date
|-----+------------
|   1 | 2001-12-20
|   2 | 2001-12-20
|   3 |
|(3 rows)
|
|rsj=> select * from test where date = null;
| key | date
|-----+------
|   3 |
|(1 row)
|
|rsj=> select * from test where date <> null;
| key | date
|-----+------
|(0 rows)
|
|rsj=> select * from test where not(date = null);
| key |    date
|-----+------------
|   1 | 2001-12-20
|   2 | 2001-12-20
|(2 rows)
--
Reason: Typo in the code
                                               _   |       _
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