As a follow-up to the debate on how to get auto-increment primary
keys:
Is it feasible to use a random number generator to generate primary
keys? I don't really need my records to have steadily increasing keys
and my number of records will presumably be much smaller than the size
of my value space (4 billion? depending on data type for prim-key). So
if I do something along the following when making a new record;
boolean created = false;
do
{
Long key = generateRandomLong();
created = ejb.create(key, contents);
}
while (!created);
(here, ejb.create() takes the primary key of the new record as its
first param and returns true if success, false if not success)
My theory is that most of the time, the creation will succeed on the
first attempt, based on the assumption that number of records is
insignificant compared to the value space of Long.
Pros:
I don't need to do manual synchronisation with a central
key-generating bean.
I don't need to do DB-specific calls to get it to generate for me.
Cons:
Unpredictable time use for creation.
Unusable if number of records becomes significant compared to value
space of Long.
I am assuming also that the creation of a random Long is a fast
process.
Cheers
Bent D
--
Bent Dalager - [EMAIL PROTECTED] - http://www.pvv.org/~bcd
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