Topic: Searching MySQL database

[-Felix-]

When I a user registers a new account, he/she must choose a user name.
Of course, I dont want two users to pick the same username, so what I need to know is how to search the MySQL table to find out if a specific user name has already been picked?

For example, a user enters desired username: Bob
So I need to search if there already is a user registered with "Bob"
How do I do this?

mysql_query("SEARCH.....") ????

[effigy]

Code: [Select]

if ( select id from table where name = '$name' yields rows ) {
  error
} else {
  continue
}

[mysqlautobackup]

$dbh =  mysql_connect('mysql_host:3306','username','password');
mysql_select_db('database');
$query = "SELECT * FROM users_table WHERE username='$username'";
$res = mysql_query($query, $dbh);
$rows = mysql_num_rows($res);

if ($rows > 0)
{
    echo 'Error!';
}
else
{
    // continue to add the user
}

mysql_close($dbh);

[ryanlwh]

why dont you just make username a UNIQUE field? Then just do a normal INSERT and check whether mysql_query is true or false. If false, then the username exists.