How can i control weather a custom transaction is executed

Question

How can i control whether a custom transaction containing delete sql statement is executed using the results of a record set?
The custom transactions dialog does no allow me to use anything more than sql and has no conditions so i cannot control flow their.
Triggers seem not to be able to access record sets defined on the same page and internally seem able to perform select staments but unable to return result sets.
Please help if you can ?

Answer 1

What exactly are you trying to do?
The following partial code-snippet checks a value on a form and performs a sql select query if a condition is met, it could perform any valid sql...
//start GWB_SetSubscribedToThread trigger
function GWB_SetSubscribedToThread(&$tNG) {
//Get the current values from the form
$threadid = $tNG->getColumnValue('NbForumMessageID');
$userid = $tNG->getColumnValue('CreatedBy');
$subscribed = $tNG->getColumnValue('Subscribe');
//Check current subscription
$query = "SELECT ms_RandomKey FROM messagesubscribe WHERE ms_MessageTypeID = 1 AND ms_ThreadID = " . $threadid . " AND ms_UserID = " . $userid ;
// This syntax doesn't work for some reason??
//$result = $tNG->connection->execute($query);
//This syntax does work
$result = mysql_query($query);
if (!$result) {
$message = 'Invalid query: ' . mysql_error() . "\n\n";
$message .= 'Query String: ' . $query;
$message = nl2br($message);
die($message);