[TYPO3] Hook doesn't work

[Georg Ringer]

Hello,

I wanted to write a small HowTo but it doesn't work as I thought because
the new data isn't written into the DB.

Explanation: There is a dropdown with tt_address-records and a checkbox
'import'.
If checkbox (row[ttaddresscheck) is activated, the own record should get
updated with
$fieldArray['name']= $row2['name'];
but this doesn't work :/
Of course I could use the Update-function but I thought this isn'
neccessary.

Can somebody please help me?
thx!
georg
PS: Here is the hook:
<?php
class tx_rghook_tcemainprocdm {
	function processDatamap_postProcessFieldArray ($status, $table, $id,
$fieldArray, $this) {
	
	if ($table == 'tx_rghook_person' && $status== 'update') {
			global $TYPO3_DB;
			$tables = "tx_rghook_person";
			$fields = "uid, ttaddress, ttaddresscheck, name, email";	
			$temp_where='uid = '.$id;
			$res = $TYPO3_DB->exec_SELECTquery($fields, $tables, $temp_where);
			$row = $TYPO3_DB->sql_fetch_assoc($res);

			if ($row[ttaddresscheck] == 1) {
	
				$tables = "tt_address";
				$fields = 'name, email';	
				$temp_where='uid = '.$row[ttaddress];
			
				$res2 = $TYPO3_DB->exec_SELECTquery($fields, $tables, $temp_where);
				$row2 = $TYPO3_DB->sql_fetch_assoc($res2);
				
				$fieldArray['name']= $row2['name'];
				$fieldArray['email']= $row2['email'];

	        		# Update
				#$update = $GLOBALS['TYPO3_DB']->UPDATEquery('tx_rghook_person',
'uid='.$id , $fieldArray); 
			        #mysql_query($update);
			}  // $row[ttaddresscheck] == 1
	} // $table == 'tx_rghook_person' && $status== 'update'

  }

} 
?>