How to avoid duplicate with MySQl in Auto-suggest - php

Question

How can I avoid duplicate return data with MYSQL with autosuggest with this code?
Thank you so much for helping
<?php
include('conn.php');
$str = strtolower($_GET['content']);
if(strlen($str))
{
$sel = mysql_query("select * from Streams where title like '".trim($str)."%'");
if(mysql_num_rows($sel))
{
echo "<table border =\"0\" width=\"100%\">\n";
if(mysql_num_rows($sel))
{
echo "<script language=\"javascript\">box('1');</script>";
while($row = mysql_fetch_array($sel))
{
$country = str_ireplace($str,"<b>".$str."</b>",($row['title']));
echo "<tr id=\"word".$row['title']."\" onmouseover=\"highlight(1,'".$row['title']."');\" onmouseout=\"highlight(0,'".$row['title']."');\" onClick=\"display('".$row['title']."');\" >\n<td>".$country."</td>\n</tr>\n";
}
}
echo "</table>";
}
}
else
{
echo "<script language=\"javascript\">box('0');</script>";
}
?>

Answer 1

What I can see in your code is that there is only a single field - title - from the SQL resultset that you are using in the PHP code. So why not instead write your query as:
"SELECT DISTINCT `title`
FROM Streams
WHERE title like '".trim($str)."%'"
Or perhaps if you can't change the query, you may store the title in a PHP array and then run array_unique on it to avoid duplicates before writing them to HTML.

Answer 2

From looking at your code, it seems like you're only using the "title" field from your database. You could do this:
$sel = mysql_query("SELECT DISTINCT title FROM Streams WHERE title LIKE '".mysql_real_escape_string(trim($str))."%'");
As per the MySQL documentation:
The [...] DISTINCT options specify
whether duplicate rows should be
returned. [...] DISTINCT specifies
removal of duplicate rows from the
result set. It is an error to specify
both options.

Answer 3

Ideally you need to select distinct elements
mysql_query("SELECT DISTINCT(title) FROM Streams WHERE title LIKE '".mysql_real_escape_string(trim($str))."%'");
Ofcourse if any reason you cant do that,
Put the data in a array and check if it was previously added to prevent duplication, define array outside the while
$data = array()
if (!in_array($row["title"], $data)){
\\do your thing
array_push($data, $row["title");
}