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Generating a unique id  RSS feed

 
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Can anyone recommend a way to generate a unique id?
 
Greenhorn
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Gonna have to be more specific...
just want a random number generated, that isnt the same as one already made, or what?
 
Peter Simard
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Yes, basically a random number that can be assigned as an id, a number not already assigned.
In PHP there's a function called uniqueID() and I've been unable to unearth anything that approximates that in JAVA, so I was wondering if there are any preferred routines to do this.
 
Sheriff
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You might want to take a look at the Servlets section of The Cattle Drive and the suggested use of DataPool from The JavaRanch Common Package.
 
Dirk Schreckmann
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Otherwise, session tracking is pretty darn easy with servlets. Again, take a look at the Servlets section of the Cattle Drive.
 
Peter Simard
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Thanks for the heads - up.
Just been fiddling with this, I'm sure it's not the best way, but it's a start...
I'm thinking something along these lines:
 
Peter Simard
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To clarify:
The id I want to generate is for a product_id field in a database, as I prefer not to rely on the auto_incrementing primary key.
I perhaps gave the impression I was looking for a session id...sorry.
 
Ranch Hand
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Here a link which claims to generate random numbers.
RandomX
Regards,
Marcel
 
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Sheriff
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Originally posted by Peter Simard:
The id I want to generate is for a product_id field in a database, as I prefer not to rely on the auto_incrementing primary key.


Why?
It seems to me as if the database was in the best position to guarantee the uniqueness of a key.
Random numbers are - by definition - not unique. You always had to check them against the database.
 
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