Re: [PHP4BETA] PHP4/PHP3 incompatability

On Fri, 17 Dec 1999, Jack Slocum wrote: > This message was sent from Geocrawler.com by "Jack Slocum" <slocum@pacbell.net> > Be sure to reply to that address. > > Is there any reason why this works in PHP3 and > not php4? I have alot of code to update if this > is not a bug: > > if($row = mysql_fetch_array($rs)) > { > $recordId = $row["recordId"]; > } > else > { > echo "Record not found"; > } > > Under php3 this is a valid way to check to see if > your query return any results and fetch the row > all in one step. In php4 it throws the following > error: > > Warning: Supplied argument is not a valid MySQL > result resource in db.php on line 27 > > Is this a bug or a new feature? :-) It's most probably neither; The query that was sent to the MySQL backend was probably invalid, which caused mysql_query() to return false (instead of a result handle), which in turn caused mysql_fetch_row() to display this error. In PHP 3.0, the warning would have been with different text, but it was illegal to use mysql_fetch_row() to check whether your query was valid there too. If your query was invalid, and mysql_query() returned false, you can't use this 'false' as a valid MySQL result handle, and doing so will generate a warning. You should check the return value from mysql_query(), if it is false, display mysql_error() to figure out why. Zeev