>Anyway, I gues it's just a question of following a standard and
>the engine according to that standard.
Your proposal would permit dupe primary keys. It's a question of
Jigal van Hemert wrote:
From: "Mikhail Entaltsev"
Before inserting MySQL will try to find a record with the same values.
But since comparison with NULL value returns always FALSE
MySQL will think that there is no such record in the table.
After this point you will get 2 identical records in the table.
MySQL as a whole seems a bit more flexible:
a UNIQUE index allows multiple NULL values (which seems to follow the NULL
handling you describe), but with BDB table only a single NULL value is
allowed in a UNIQUE index (so MySQL seems to be able to find a NULL value in
Anyway, I gues it's just a question of following a standard and optimizing
the engine according to that standard.