I believe one of the reasons is that many times you want to know the ID of your new record. For example, you inserted a new file to the 'files' table, and you would like to store a reference to it in your xyz table.
<br><br>For mysql there is mysql_insert_id(), but not for others.<br><br><div><span class="gmail_quote">On 4/25/07, <b class="gmail_sendername">Syscrusher</b> &lt;<a href="mailto:syscrusher@4th.com">syscrusher@4th.com</a>
&gt; wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">On Wednesday 25 April 2007 10:29, Ezra B. Gildesgame wrote:<br>&gt; I happened to discuss this with Greg Knaddison yesterday.
<br>&gt; MySQL 4 does not support auto-incrementing columns.<br><br>I must respectfully disagree. I happened to have a copy of the MySQL<br>reference book from version 3.22 sitting on my bookshelf, and AUTO_INCREMENT<br>was supported even then. :-) Never mind the question of why I still have such
<br>an old book....<br><br>I also checked a PostgreSQL reference book, and they offer a SERIAL<br>column type that works very similarly to the AUTO_INCREMENT in MySQL. I don&#39;t<br>know how far back this support goes; my book is for PG version 
8.something and<br>was copyright 2006.<br><br>I can&#39;t comment on the Microsoft SQL Server implementation of this, if any,<br>because I don&#39;t have any manual for that here.<br><br>Scott<br><br>--<br>-------------------------------------------------------------------------------
<br>Syscrusher (Scott Courtney)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Drupal page:&nbsp;&nbsp; <a href="http://drupal.org/user/9184">http://drupal.org/user/9184</a><br>syscrusher at 4th dot com&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Home page:&nbsp;&nbsp;&nbsp;&nbsp; <a href="http://4th.com/">http://4th.com/
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