Array_Unique problem

neroag

Hi all
I have a call to a database table the results stored what i thought into an array that has many duplicates, im just trying to remove the duplicates using the following code but it just returns an error ...

Warning: array_unique() [function.array-unique]: The argument should be an array in......

$query = "SELECT * FROM classes"; 
$result = mysql_query($query) or die(mysql_error());
while($row = mysql_fetch_array($result)){
	$class = $row['class'];
}
$result = array_unique($class);
echo $result;
	echo "<br />";

I would appreciate is someone could correct my errors if possible plz
Many thanks

laserlight

The problem is that $class is not an array, but is assigned the last value of $row['class']. The fix is easy:

$query = "SELECT * FROM classes";
$result = mysql_query($query) or die(mysql_error());
$class = array();
while ($row = mysql_fetch_array($result)) {
    $class[] = $row['class'];
}
$result = array_unique($class);
print_r($result);

However, even better than using array_unique would be to change the SQL statement to SELECT DISTINCT(class) FROM classes.

bpat1434

Not to mention that array_unique() won't do a recursive search, so setting each element of the $class array to an array of values from MySQL means that array_unique() won't recurse into the secondary array and look at those values. You have to write your own function to do that.

laserlight

Not to mention that array_unique() won't do a recursive search, so setting each element of the $class array to an array of values from MySQL means that array_unique() won't recurse into the secondary array and look at those values. You have to write your own function to do that.

That is not a problem in this case though, each element of $class is set to $row['class'], not $row.

bpat1434

ah... didn't see that 🙂