sorting - yii sort by a custom attribute -

in vacation model vac have function

public function getvaccount(){ 

this function returns how many days there in 1 vacation.

and want add custom column cgridview this:

   <?php     $this->widget('zii.widgets.grid.cgridview', array(             ...             array(                 'name' => 'count',                 'value' => '$data->getvacperiod()'             ),             ...         ),     ));     ?> 

it works fine. don't know how can sort upon custom attribute. tried use csort not work. idea?

to use csort sorting, you'll need convert vacation function sql query , stash results in public variable in model.

csort works sql statements/functions, underneath it's using order sorting.

more info (and demo code) available here

here's sample of how i'm doing on site of mine:

$criteria->select = array(         "*",         new cdbexpression("if(survey.requestdate, survey.requestdate, surveycompletedate) surveydate")     ); 

this allows me type of filter:

return new cactivedataprovider($this, array(     'criteria' => $criteria,     'sort'=>array(         'attributes'=>array(             'surveydate' => array(                 'asc' => 'surveydate',                 'desc' => 'surveydate desc',             ),             '*',         ),     ), ); 

note: you'll need public variable defined in model hold results of cdbexpression you're doing. mine called surveydate.