I know about the existence of LAST_INSERT_ID() function... Though I am not quite sure about its behaviour... Does it take the last inserted id from the current user into account? Or uses all the sessions as reference? If the later holds true I am afraid another query by another user modifies such value before using such data. Are there any alternative ways to do this without recurring MAX()?

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    answer to ur first question can be found here and for your second question this post may be useful
    – Masoud
    Commented Jul 1, 2015 at 6:47

1 Answer 1


From here: (My emphasis below)

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.

A fundamental point about LAST_INSERT_ID() is that bit about per_connection - if it wasn't on that basis, then the function would be useless in a multi-user environment.

Unless there are further complications, you have absolutely no need to resort to the MAX() function - and you have no guarantee anyway that (in a multi-user scenario), your MAX(xxx) value won't be incremented by another user in the instant after you call it.

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