Sorting with CSqlDataProvider in yii

Question

I need to get some records from a table called Hospitals with the same criteria:

First get the ones which city match with $city param. Second get the ones which state match with $state param. Third get the rest ordered by AZ

I need to get all of them in one query since I'm going to paginate the resulset, so i choose CSqlDataProvider, which receives a sql, the count and the pagination as initial configuration: http://www.yiiframework.com/doc/api/1.1/CSqlDataProvider

so, I was thinking of making extra fields as booleans and sort them by theese, like: same_city, same_state.

so let's assume this is the resulted sql (when i replaced with params values from request) that goes to the CSqlDatProvider:

select *, 
IF(city like '%San Antonio%', 1, 0) as same_city, 
IF(state=44, 1, 0) as same_state 
from hospitals 
order by same_city DESC, same_state DESC, hospital_name ASC;

If i assign this string to the CSqlDataProvider i won't be able to paginate since I'm hardcoding the order... however I need this specific order so the criteria of records retrieving is successful.

$arHospitals = new CSqlDataProvider($sql, array(
    'totalItemCount'=>$count,
    'pagination'=>array(
        'pageSize'=>30,
    ),
));

if I run the code above, it will return the whole matching records, no matter of pageSize. However if I use the pagination according to yii documentation, I will get only the records that pagination indicates, but with a non-sense order for me... I need the following order in the fields: same_city DESC, same_state DESC, hospital_name ASC.

$arHospitals = new CSqlDataProvider($sql, array(
    'totalItemCount'=>$count,
    'sort'=>array(
        'attributes'=>array(
            'asc'=>array('hospital_name'),
            'desc'=>array('same_city', 'same_state'),
        ),
    ),
    'pagination'=>array(
        'pageSize'=>30,
    ),
));

Any ideas of how to solve this? If I'm missing some key information about the problem please let me know.

Answer 1

Something like this should work:

$arHospitals = new CSqlDataProvider($sql, array(
    'totalItemCount'=>$count,
    'sort'=>array(
        'attributes'=>array(
            'virtualFieldName'=>array( //virtual field name
                //give no possibility to sort in any other order than
                'asc'=>'same_city DESC, same_state DESC, hospital_name ASC', 
                'desc'=>'same_city DESC, same_state DESC, hospital_name ASC', 
                'label'=>'Default Sort Order'
            ),
        ),
        'defaultOrder'=>array(
            'virtualFieldName'=>CSort::SORT_ASC, //default sort value
        ),
    ),
    'pagination'=>array(
        'pageSize'=>30,
    ),
));

See http://www.yiiframework.com/doc/api/1.1/CSort#attributes-detail for more info.