Get id of a row in a php table

[danielalm]

    <?php
                    $idofrow = $_GET['buyid'];
                    $checkifpurchased = mysql_query("SELECT * FROM sales WHERE buyer='$userid' AND sellerid='$sellerid' AND itemsold='$idofrow'") or mysql_error();
 
                    if($sellerid=$userid) {
                        echo "Owner";
                    }
                    else if(mysql_num_rows($checkifpurchased) != 0){
                        echo "Purchased";
                    }
                    else if($useridpointvalue < 1){
                        echo "<a href='mypoints.php'>Insufficient Funds</a>";    
                    }
                    else{
                        ?>
                        <a href="javascript:confirmbuy(<?php echo $noteid; ?>);" >Buy</a>
                        <?php
                    }
                    ?>    

I have 3 tables in my db. Book, Sales, and Users. My only problem is getting the exact row in the table that they want to buy to check it against the sales table and displaying purchased. The javascript works for finding the row, so after the book is purchased it shows "purchased" until you refresh. The variable idofrow gets the value from the javascript.

[AyakaNamase09]

use the limit in mysql_query like this mysql_query("Select * from table where id="'.variable.'" limit 1"); it might be a little help