Change this to use SQL

Hi,

I want to change this so instead of using the values that is there e.g. if ( $username == "joe" || $username == "rony" || $username== "joo" ) I want to search a MySQL table called users to see if there is a match.

<?
$action = trim($HTTP_GET_VARS['action']);
?>
<?
switch ( $action ):
 case 'validateUsername':
   $username = trim($HTTP_GET_VARS['username']);
   if ( strlen($username) >= 3 ){
   	   if ( $username == "joe" || $username == "rony" || $username== "joo" )
			print "<font color=GREEN>Username is valid</font>";
	   else
			print "<font color=RED>Username is not valid</font>";
	}
	else{
		print "<font color=RED>Username must be longer then 3 characters</font>";
	}
 break;
 default:
 //silence is golden
endswitch;
?>

Code (markup):

Thank you in advanced for your help.
Cheers,
Adam

 

Hi,

you can probably try this

SELECT * FROM users WHERE name_of_field IN ('joe','rony','joo')

OR

SELECT * FROM users WHERE name_of_field = 'joe' OR name_of_field = 'rony' OR name_of_field = 'joo'

 

Sorry i did not explain my self properly, what i meant is i want to check if the POST user name exists in the users table. So i don't want to check with certain names just all entries.

 

oh ok,

try this then

SELECT * FROM users WHERE name_of_field = '".$_POST['form_field_name']."'"

Note: having the post directly in the query is not at all safe but i've used it here for brevity

 

$result = mysql_query("SELECT * FROM users WHERE  user_name='$_POST[username]'");
if(mysql_num_rows($result)){
// show error msg here
}
else
{
// welcome new user 
}

PHP:

 

I have now done this but it tell me the username is available even if it is not.

<?php
include("config/db.config.php");
$action = trim($HTTP_GET_VARS['action']);

switch ( $action ):
 case 'validateUsername':
   $username = trim($HTTP_GET_VARS['username']);
   if ( strlen($username) >= 3 ){
   
   $result = mysql_query("SELECT * FROM users WHERE username='$_POST[username]'");
		if(mysql_num_rows($result)){
		print "<font color=RED>Username has already been taken.</font>";
		}else{
		print "<font color=GREEN>Username is available</font>";
		}

	}else{
		print "<font color=RED>Username must be longer then 3 characters</font>";
	}
 break;
 default:
 //silence is golden
endswitch;
?>

Code (markup):