PDO :: lastInsertId（）可能不准确吗？ [重复]

Question

This question already has an answer here:

• MySQL and PDO: Could PDO::lastInsertId theoretically fail? 2 answers

I've got a page calling a script via AJAX which could be asynchronously called multiple times simultaneously from the same parent page. This script uses require_once to access a configuration script with the database handler. Will the script call a unique instance of this handler each time, or if multiple copies are open will they all be using the same instance and causing undesirable results when I attempt to get the ID of the last insert from that instance of the script?

Just to be clear, this is the command I'm referencing:

$DBH->lastInsertId()

Thanks!

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Answer 1

As noted in the documentation:

Note: This method may not return a meaningful or consistent result across different PDO drivers, because the underlying database may not even support the notion of auto-increment fields or sequences.