Rene Veerman wrote:
Hi.
I'm looking for the most efficient way to insert several records and
retrieve the auto_increment values for the inserted rows, while
avoiding crippling concurrency problems caused by multiple php threads
doing this on the same table at potentially the same time.
Any clues are greatly appreciated..
I'm looking for the most sql server independent way to do this.
Rene
The 'correct' way of doing this is to use a 'sequence' which is something
introduced in newer versions of the SQL standard. Firebird(Interbase) has had
'generators' since the early days (20+ years) and these provide a unique number
which can then be inserted into the table.
ADOdb emulates sequences in MySQL by creating a separate table for the insert
value, so you can get the next value and work with it, without any worries. The
only 'problem' is in situations were an insert is rolled back, a number is lost,
but that is ACTUALLY the correct result, since there is no way of knowing that a
previous insert WILL commit when several people are adding records in parallel.
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Lester Caine - G8HFL
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