Update a row if ID exists else Insert

[beltinge]

This is the code of a .php file. The column "memberid" has a unique index. When a user enters a record with an existing memberid, the record must get updated else a new row is created.I also want to show an alert box. For test purposes I added like the way below, but it is not firing. No message is displayed.I also want to know whether it is the right approach to handle insert/update automatically?\[code\]<META http-equiv="refresh" content="2; URL=socialprofile.html"><?phperror_reporting(E_ALL ^ E_NOTICE);require_once("../Lib/dbaccess.php"); //Retrieve values from Input Form $CandidateID = $_POST["inCandidate"]; $SocialProfile = $_POST["inActivities"]; $InsertQuery = "INSERT INTO candidate_db_social (memberid, socialactivities, lastupdated) VALUES (".$CandidateID.",'".$SocialProfile."',now())"; $UpdateQuery = "UPDATE candidate_db_social SET socialactivities='".$SocialProfile."', lastupdated=now() WHERE memberid=".$CandidateID; try { $Result = dbaccess::InsertRecord($InsertQuery); } catch(exception $ex) { $Result = dbaccess::InsertRecord($UpdateQuery); echo "<script type='text/javascript'>alert('".$ex."');</script>"; }?>\[/code\]