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Better way to determine if a query has returned at least one row


Scaryminds

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Am currently using this code, and actually thinking about it should split the query to an include in order to allow for other database drivers, on the chance we may decide to ditch the old MySQL. But I digress from the question.

 

		include($lib."dbconfig.php");

		$q = 'SELECT * FROM file WHERE this = "'.$that'";
		$result = mysql_query($q);

		if (mysql_num_rows($result) > 0) 

 

If the query doesn't pick up a row I'm getting this error yo,

 

Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in D:\webpages\*\*\admin.php on line 553

 

So what would be a better way of testing if the query was successful?  :shrug:

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Your query has a syntax error in it, so the mysql_query() function is returning "false". Change the query to

<?php
$q = "SELECT * FROM file WHERE this = '$that'";
?>

and change the next line to

<?php
$result = mysql_query($q) or die("Problem with the query: $q<br>" . mysql_error());
?>

at least while you're debugging your code.

 

Ken

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Hey thanks Ken,

 

Did cut down the query as it was quite long and involved, but adding your die clause got the root issue :)

 

Unknown column 'question' in 'where clause'

 

d'uh! Been a while since I worked on the software and there are clearly some bugs we never got around to fixing  :P

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