View Full Version : Finding out the highest number in an auto-incrementing table
01-21-2012, 10:24 AM
I have a row in a MySQL table called id, which auto-increments.
I was wondering if anyone knows a PHP solution to find out what the highest number in the row is?
I am thinking perhaps execute a MySQL query that will list the highest number, and then echo the result, like $row[id] in PHP?
01-21-2012, 12:06 PM
* Define $server, $username, $password, $database and $table here as follows:
* $server = name of mysql server.
* $username = username for mysql account.
* $password = password for mysql account.
* $database = name of database to use.
* $table = name of table containing the id column.
$conn = mysql_connect($server, $username, $password);
$res = mysql_query("select max(id) from $table;");
$data = mysql_fetch_array($res);
$count = $data;
Of course, you'll need to put some error checking in, but what I've posted above is the basic code to do what you want.
01-21-2012, 12:23 PM
Let me ask, what's your ultimate goal? It looks like you are after a wrong path.
01-21-2012, 01:15 PM
You can also use:
select id from <table> order by id desc limit 1
01-21-2012, 10:47 PM
Do you want the highest number there or do you want the one your script just inserted?
If the latter then you want "SELECT LAST_INSERT_ID()"
That function retrieves the last value actually inserted by the currently running copy of the script and will ignore any higher numbers inserted by someone else since you inserted yours.
Powered by vBulletin® Version 4.2.2 Copyright © 2015 vBulletin Solutions, Inc. All rights reserved.