Renaming an image during the uploading PHP Mysql

Using the following code could someone explain to me how I can rename the image files to a misc name during the upload process?

Here is what I'm working with.

uploader.php

<?php
include($_SERVER['DOCUMENT_ROOT'] . "/connections/dbconnect.php");
$dataType = mysql_real_escape_string($_POST["dataType"]);
$title = mysql_real_escape_string($_POST["title"]);
$fileName = basename($_FILES["image"]["name"]);
$target_path = ($_SERVER['DOCUMENT_ROOT'] . "/images/gallery/".$fileName);
if (file_exists($target_path))
{
    echo "An image with that file name already exists.";
}
elseif (move_uploaded_file($_FILES["image"]["tmp_name"], $target_path))
{
    // The file is in the images/gallery folder. Insert record into database by
    // executing the following query:
     $sql="INSERT INTO images (data_type, title, file_name)"."VALUES('$dataType','$title','$fileName')";
     $retval = mysql_query($sql);

    echo "The image was successfully uploaded and added to the gallery :) <a href='index.php'>Add another image</a>";


}
else
{
    echo "There was an error uploading the file, please try again!";
}
?>

Then here is my code for uploading the image to the gallery.

<form enctype="multipart/form-data" action="uploader.php" method="POST">


        Category: <select class="text" name="dataType">
        <option value="treeremoval" selected="selected">treeremoval</option>
        <option value="treetrimming" >treetrimming</option>
        <option value="treebracing" >treebracing</option>
        <option value="stumpgrinding" >stumpgrinding</option>
        <option value="firewood" >firewood</option>
        <option value="cleanup" >cleanup</option>
        </select><br />
<br />




    Caption: <input type="text" name="title"><br />
<br />

    Image to upload: <input type="file" name="image"><br />
<br />




    <input type="submit" value="Upload">
</form>

I am very new to using php and mysql so any help would be appreciated. I have some other questions too, but I guess I should ask one at a time. =)

Thank You!

Solution

I would try something like this, you will create a unique id and append the extension of the file to it, if that name exists you loop until you have one that doesn't, then you move the file.

<?php
include($_SERVER['DOCUMENT_ROOT'] . "/connections/dbconnect.php");

$dataType = mysql_real_escape_string($_POST["dataType"]);
$title = mysql_real_escape_string($_POST["title"]);

$fileData = pathinfo(basename($_FILES["image"]["name"]));

$fileName = uniqid() . '.' . $fileData['extension'];

$target_path = ($_SERVER['DOCUMENT_ROOT'] . "/images/gallery/" . $fileName);

while(file_exists($target_path))
{
    $fileName = uniqid() . '.' . $fileData['extension'];
    $target_path = ($_SERVER['DOCUMENT_ROOT'] . "/images/gallery/" . $fileName);
}

if (move_uploaded_file($_FILES["image"]["tmp_name"], $target_path))
{
    // The file is in the images/gallery folder. Insert record into database by
    // executing the following query:
     $sql="INSERT INTO images (data_type, title, file_name)"."VALUES('$dataType','$title','$fileName')";
     $retval = mysql_query($sql);

    echo "The image was successfully uploaded and added to the gallery :) <a href='index.php'>Add another image</a>";


}
else
{
    echo "There was an error uploading the file, please try again!";
}