How can you use the SUM of the column in other element calc in the same list?

[jorgeiba]

How can you use the SUM of the column in other element calc in the same list?

Thanks for all!

 

[NickC4555]

If you mean the sum of all rows in a list for a given element, like this. You could add a where clause if you wanted to.

$db = JFactory::getDbo();
$query = $db->getQuery(true);
$query->select('sum('.$db->quoteName('column_name').')');
$query->from($db->quoteName('#__table_name'));

$db->setQuery($query);
$result = $db->loadResult();

return $result;

 

[jorgeiba]

Thanks NickC4555!

You know if you can use placeholder in this code or not? ex: {table_name___elementname}

Thanks for all!

 

[NickC4555]

You can use placeholders in code, don't forget to put them in single quotes if they are for string values.

 

[jorgeiba]

Thanks NickC4555!

 

[cheesegrits]

You can use placeholders in code, don't forget to put them in single quotes if they are for string values.

It's best to use quotes even for values you expect to be numbers, in case they are empty. And if necessary, cast them appropriately ...

$foo_int = (int)'{mytable___some_integer}';
$foo_float = (float)'{mytable___some_decimal}';

That way, if the placeholder is empty, you get 0 rather than a syntax error, as the resulting code being eval'ed is ...

$foo_int = (int)'';

... which yields 0, rather than ...

$foo_int = ;

... which is an error.

-- hugh