[support] Printing "0" when a db query returns nothing

[Neil Coghlan]

the file_downloads table only has records of files that have been downloaded so User A may have created 3 content pages with an attachment on each, but if they haven't been downloaded, he will have no record in the file_downloads table.

that's why it was returning no results...I don't know enough about mysql to say whether it was actually returning NULL or no result, but the solution offered by Jamie (print (int) $output->DownloadCount;) seems to be working now, with a "0" printed if a user has no records in the file_downloads table.

Neil


----- Original Message ----- 
From: "Ivan Sergio Borgonovo" <mail at webthatworks.it>
To: <support at drupal.org>
Sent: Friday, April 09, 2010 2:58 PM
Subject: Re: [support] Printing "0" when a db query returns nothing


> On Fri, 9 Apr 2010 13:49:43 -0300
> "Neil Coghlan" <neil at esl-lounge.com> wrote:
> 
>> I am trying to print the number of downloads a user's attachments
>> have produced and am 95% there. I just don't know how to print
>> zero if the SUM returns nothing.
> 
> I'd check why a sum() is returning null before casting in php.
> 
> sum() is going to return a 0 if NO record was returned.
> That means there is at least one count that is null (and some may
> not be), a null in a sum is enough to nullify the sum. 10 + null =
> null.
> 
> select sum(coalesce(count, 0))...
> You'd be better to set default 0 on files_download.count and update
> the null record to 0.
> 
> -- 
> Ivan Sergio Borgonovo
> http://www.webthatworks.it
> 
> -- 
> [ Drupal support list | http://lists.drupal.org/ ]
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.drupal.org/pipermail/support/attachments/20100409/4002c112/attachment.html