The DB will create a unique id for each row whether I tell it do that or not. When I do an INSERT and then ask: my $cur_id = $dbh->last_insert_id; the DB gives me an id for my $dbh connection handle. This will work even if there are multiple writers to the DB. I should not increment that number or screw around with it in any way - it could be that 14 more inserts have happened in the meantime. This id number will be for the last insert that my connection did. I can use that number to write (INSERT) additional rows into another table within the DB. If I run the initial write and then id query and subsequent writes all as one transaction, then in theory with an ACID compliant DB, all will be fine. In practice that is not true because of the way the hardware works - different subject...

There is no easier way to get a unique number than to ask the DB to do it for you. This avoids all sorts of complications like you mentioned. "autoincrement" does not mean that my id numbers, for my connection will be sequential. This just tells the DB to generate these numbers on its own.

In reply to Re^2: Perl DBI and Foreign Keys by Marshall
in thread Perl DBI and Foreign Keys by Marshall

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