[TYPO3-core] Checking return values of SQL query - see bug#3794

[Martin Kutschker]

Hi!

Bug http://bugs.typo3.org/view.php?id=3794 complains about a PHP warning in 
  t3lib\class.t3lib_page.php:getHash().

It's a classic SELECT and fetch but don't check result. Is it worth the 
hassle to check if the result is a valid handle (ie not FALSE)?

Code woud look like this (plus a new check for a cache miss (returns FALSE).

$res = $GLOBALS['TYPO3_DB']->exec_SELECTquery('content', 'cache_hash',
   'hash='.$GLOBALS['TYPO3_DB']->fullQuoteStr($hash, 'cache_hash').
   $whereAdd
);
if ($res!==FALSE && $row = $GLOBALS['TYPO3_DB']->sql_fetch_assoc($res))	{
   $GLOBALS['TYPO3_DB']->sql_free_result($res);
   return is_array($row) ? $row['content'] : FALSE;
}

The FALSE on miss is a new idea (not in the bug report), but it might be 
nice to distinct between miss and an empty string as content in the cache.

Masi