Question

I am using adodb for PHP library.

For fetching the id at which the record is inserted I use this function

"$db->Insert_ID()"

I want to know if there are multiple and simultaneous inserts into the database table, will this method return me the correct inserted id for each record inserted ?

The reason I am asking this is because I use this last insert id for further processing of other records and making subsequent entries in the related tables.

Is this approach safe enough or am I missing something.

Please help me formulate a proper working plan for this so that I can use the last insert id for further inserts into the other table safely without having to mess up with the existing data.

Thanks

Answer 1

Yes, it’s safe for concurent use. That’s because LAST_INSERT_ID() is per-connection, as explained here:

The ID that was generated is
maintained in the server on a
per-connection basis. This means that
the value returned by the function to
a given client is the first
AUTO_INCREMENT value generated for
most recent statement affecting an
AUTO_INCREMENT column by that client.
This value cannot be affected by other
clients, even if they generate
AUTO_INCREMENT values of their own.
This behavior ensures that each client
can retrieve its own ID without
concern for the activity of other
clients, and without the need for
locks or transactions.