From: Daevid Vincent
Date: July 21 2011 7:13pm
Subject: RE: Next Unique Number - Generation
List-Archive: http://lists.mysql.com/mysql/225405
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I can think of several ways to accomplish this (or close to it).

 * Assign each server a number and prefix/append that number to the =
unique
ID.
 * initialize each table on each server at a different huge number so =
they
don't ever collide:
		ALTER TABLE `students` AUTO_INCREMENT=3D10000000;
	Other server:
		ALTER TABLE `students` AUTO_INCREMENT=3D20000000;
 * don't re-invent the wheel and just use UUID()
 * make the primary key a combination key of a regular auto-increment =
and
NOW() or RAND() or some other unique column of the table itself or =
something
like IP number of the server, etc.
 * setup a trigger to alter the primary key accordingly prior to insert.
Maybe one server is even numbers and the other is odd numbers, or use =
MOD()
or other math to have a pool of servers.
http://stackoverflow.com/questions/5416548/mysql-two-column-primary-key-w=
ith
-auto-increment


> -----Original Message-----
> From: Vikram A [mailto:vikkiatbipl@stripped]
> Sent: Wednesday, July 20, 2011 11:18 PM
> To: MY SQL Mailing list
> Subject: Next Unique Number - Generation
>=20
> Hi there,
>=20
> I need a technical help fro you,
> I have developed a software for college & school. Here we have concept
> called register number/admission number. These are =
two=A0unique=A0umber for
each
> student. My=A0application=A0resides Client/server model.
> These numbers will be generated (some defined format) to each student =
when
> they are=A0admitted at first time. This admission process is taken =
place at
> different nodes at a time.
> In this=A0scenario, I am facing=A0difficulty that, the same number is
generated
> at time in two machines. (Logic is newest number will =
be=A0displayed=A0in the
> node before admission).
>=20
> How can I stop this logical issue?
> Can i have solution for this?
>=20
> Thank you in advance.