Re: Differentiate Between Zero-Length String and NULLColumn Values

D'Arcy J.M. Cain wrote:
>    SELECT * FROM table WHERE column IS NULL;
>    SELECT * FROM table WHERE column = NULL;
>
> The latter violates the SQL spec and is not allowed by PostgreSQL
> without setting a special flag.

It doesn't violate any spec and it's certainly allowed by PostgreSQL 
without any flags.  It's just that the result is not what some people 
expect.

-- 
Peter Eisentraut
http://developer.postgresql.org/~petere/