Subject Re: [firebird-support] Re: Why NULL <> NULL ?
Author Dave Hughes
On Thu, May 18, 2006 15:47, jasajona wrote:
> --- In, Paul Vinkenoog <paul@...> wrote:
>> And as others said, use COALESCE.
> Who created this strange name for this function? Since this function
> appeared in FB, every time when I want to use it, I have to look
> somewhere to find how to write it :)

Actually, I think the SQL standard "invented" the name. Consider what else
implements the COALESCE function:

* IBM DB2 (which also uses VALUE as a synonym)
* MS SQL Server (which also has ISNULL, but that only takes two arguments
instead of an arbitrary number)
* Oracle (which also has NVL, again this only takes two arguments instead
of an arbitrary number)
* PostgreSQL
* and, of course, Firebird

Furthermore, from the PostgreSQL documentation:

"This SQL-standard function provides capabilities similar to NVL and
IFNULL, which are used in some other database systems."

Hence, while you might argue that the SQL standard has chosen a silly name
(and I might even be inclined to agree with you to an extent ... it is a
mite unwieldly) I doubt you have cause to complain to the Firebird
developers about it; they're likely trying to follow the standard (or at
least the consensus) and in this case that's no bad thing.

A similar argument can be raised re: your earlier comments on Firebird's
handling of NULL comparisons.



Dave Hughes