Best way to find the last inserted ID in mysql using php

问题

Im wondering as to what the best solution is to get the last inserted ID after a mysql inquiry?

I have found the following solutions :

<?php
function get_current_insert_id($table)
{
    $q = "SELECT LAST_INSERT_ID() FROM $table"; 
    return mysql_num_rows(mysql_query($q)) + 1;
}
?>

or even using mysql_insert_id php function, but apparently this function will not work well with bigint (thats what I am using for ID field) and if there are alot of consecutive sql inquiries it could be unreliable.

Could someone provide a reliable and fast solution to achieve this task?

回答1:

Isn't SELECT LAST_INSERT_ID() reliable and safe enough?

From MySQL Doc: 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.

Note from a forum: (...)All bets are off, though, if for some reason you are using persistent connections, such as via mysql_pconnect()(...)

回答2:

If you insert multiple rows using a single INSERT statement, LAST_INSERT_ID() returns the value generated for the first inserted row only. The reason for this is to make it possible to reproduce easily the same INSERT statement against some other server.

来源：https://stackoverflow.com/questions/10371306/best-way-to-find-the-last-inserted-id-in-mysql-using-php