Checking a unique username

[peuge]

I am using a function which checks if a username is unique in a database. I have the following:

 

function check($table, $field, $compar_to)
{
  $sql = "SELECT  '.mysql_real_esacape_string($field).'
          FROM '.mysql_real_escape_string($table).'
          WHERE "'.mysql_real_escape_string($field).'" = "'.mysql_real_escape_string($compar_to).'"";

  $query = mysql_query($sql);

if(mysql_num_rows($query)==0)
{
	return TRUE;
}
else 
       {
	return FALSE;
}
}

 

The error code I get is this:

Parse error: parse error, unexpected T_CONSTANT_ENCAPSED_STRING in D:\Programs\EasyPHP 2.0b1\www\DataBase\functions.php on line 12

 

and I call the function via this:

checkUnique($tbl_name,'username', $_POST['myusername'])

 

The above function is in an if loop and the condition is if this is true then do X.

 

Thanks

[rhodesa]

You can't start a string with a double quote then end with a single quote. You query should be:

 

<?php
  $sql = "SELECT  `".mysql_real_esacape_string($field)."`".
          " FROM `".mysql_real_escape_string($table)."`".
          " WHERE `".mysql_real_escape_string($field)."` = '".mysql_real_escape_string($compar_to)."'";
?>

 

[rhodesa]

Also, you declare your function as 'check' but you call it as 'checkUnique'

[peuge]

Stupid should have seen that. Thanks! It works