From: Gary W. Smith (garyprimeexalia.com)
Date: Wed Feb 25 2009 - 16:10:56 CST

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Not sure that this is the problem BUT you should probably qualify the name of the variable such that "SELECT MAX(id) AS id FROM book". But you don't want "max(id) as id" but rather "max(id) + 1 as id". With that you can then just return the final value. Also, if you don't want to alias the value (or whatever it's called) you should use $row[0] to get it by ordinal posistion.
 
As for now wanting to use autoincrement, you can run into a race condition where two people are inserting at the same time, thus having the same generated id.
 
Hope that helps.
 

________________________________

From: PJ [mailto:af.gourmetvideotron.ca]
Sent: Wed 2/25/2009 2:01 PM
To: MySql; php-generallists.php.net
Subject: non-auto increment question

I want to insert a new table entry 1 number higher than the highest in
the field (id). I cannot use auto-increment.
And I want to show the value of the field to be added in an input field
on the web page:
if (isset($_REQUEST["AddNewBooksRequest"])) {
    $SQL = "SELECT MAX(id) FROM book";
        $result = mysql_query($sql, $db);
        $bookCount = mysql_num_rows($result);
            for ($i=0; $i < $bookCount; $i++) {
            $row = mysql_fetch_array($result);
            $idIN = $row["id"]+1;
            }
    $idIN = $_POST["idIN"];
    $titleIN = $_POST["titleIN"];

...snip...

<td colspan="2">
<?
echo "<input type='text' name='titleIN' value='$idIN' disabled size='2'>";
?>
</td>

What am I doing wrong? (The query works and returns the right nr. but
what do I have to do to add 1 to that number and then display it in the
on page and post it to the table?

--

Phil Jourdan --- pjptahhotep.com
   http://www.ptahhotep.com <http://www.ptahhotep.com/>
   http://www.chiccantine.com <http://www.chiccantine.com/>

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