Newbie Questions

[Anon]

I have two newbie questions..
1. How do I query last record from an auto_increment column in a table?
2. How do I check existing data and print an error if the data exists?
Thank you..

[craigh]

1. I think there is a faster way to do this but this would work:

SELECT * from table_name ORDER BY table_id DESC LIMIT 1

[crowezr]

1. If you are using mySQL and want just the auto_increment field value to be returned, you can use the mysql_insert_id() function.

$connection = mysql_connect("localhost", "","");

$query = "INSERT INTO user(login,password) VALUES('username', 'password') ";
$result = mysql_query($query, $connection);

print("Auto increment is " . mysql_insert_id($connection));

2. $query = "SELECT username FROM users WHERE username = 'john' ";
   $result = mysql_query($result,$connection);

$row = mysql_fetch_array($result);

if($row != "")
{
print("The username exists!");
}
else
{
print("The username is available.");
}

[junebug]

for the last record of an auto-increment do this:

select max(id) from table;

for checking and printing an error message:

$query = "select field from table where field = '$value'";
$result = mysql_query($query);
if($result == $value)
{
print "error message";
}
else
{
print "non-error message";
}

[Anon]

Great..
How stupid I am...
Thanks a lot guys...