Make a table in your database called ID
Create table ID (ID bigint auto_increment not null,
lockedBy varchar(10) null};
Then write code in your favorite language that:
Checks to see if the record is locked by another user. if so, loop.
Updates the record with a unique session identifier (IP ADDRESS?) in the
LockedBy field.
Checks to see that the lock on the record is theirs. If not, loop.
Grab the current value in the ID field and store it for use.
Update the record by incrementing the ID by 1 and erasing the lock on the
record.
This should allow you to have a "Serial Assigned Key" or SAK global to your
database. If you need it to span databases then I suggest you put this table
in it's own database.
Cal
http://www.calevans.com
-----Original Message-----
From: Jean-Philippe Côté [mailto:[EMAIL PROTECTED]]
Sent: Monday, April 09, 2001 11:40 PM
To: [EMAIL PROTECTED]
Subject: Global AUTO_INCREMENT ???
Hi everybody,
I'm new to MySQL and I'm trying to figure out a way of
automatically generating a sequence of unique id numbers
in many tables. I need to get new id's at any time
and possibly from different connections. As I understand,
AUTO_INCREMENT does this, but the sequence it generates
is not global. That is, if table T1 and T2 have AUTO_INCREMENT
id columns, then a row in T1 could have the same id as
a row in T2. I think I could circumvent this by setting
the AUTO_INCREMENT sequence so that it starts at say 1000000
in T1, 2000000 in T2, 3000000 in T3 and so on. The chances
that rows in different tables have the same id would be
rather slim. But I don't really like this solution. Does anybody
knows a cleaner and nicer way of doing this ?
Thanks in advance.
J-P
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