[Wiki] Sort and filter a custom or composite CGridView column - that may even contain data from different tables.

class account_model extends CActiveRecord
{
    /* Gridview Attributes */
    public $varFullname;
 
    /* Own defined Getter function to combine fields */
    public function getCompiledFullname()
    {
        /* Test if account is linked to a Client. If not, use account_description, otherwise use client names and surname. */
        if ($this->client !== null)
        {
            return  
                $this->client->client_surname . ' ' .
                $this->client->client_name1 . ' ' .
                $this->client->client_name2 . ' ' .
                $this->client->client_name3;
        }
        else
        {
            return $this->account_description;
        }
    }
 
    public function relations()
    {
        return array(
            'client' => array(self::HAS_ONE, 'client', 'accnt_nr'),
        );
    }
 
    public function rules()
    {
        return array(
            array('varFullname', 'safe', 'on'=>'search'),
        );
    }
 
    public function attributeLabels()
    {
        return array(
            'account_description' => 'Name',
        );
    }
 
    public function search()
    {
        $criteria       = new CDbCriteria;
        $sort           = new CSort;
 
        /* Eager loading if Account has a Client */
        $criteria->with = array(
            'client' => array()
        );
 
        /* Filter criteria 
        Testing for null values is important because unused name fields
        will be null and they will filter out records if untreated.
 
        The following compare statement works like this:
        if(account_description == null)
        then (use surname and names in comparison)
        else (use account_description in comparison).
        Compare them to $this->varFullname.  
 
        Note: IFNULL = MySql; ISNULL = SQL Server*/
 
        $criteria->compare(
            "IFNULL(account_description,
                CONCAT( IFNULL(client_surname,''),
                        IFNULL(client_name1,''),
                        IFNULL(client_name2,''),
                        IFNULL(client_name3,''))
            )", $this->varFullname, true);
 
        /* Sort criteria */
        $sort->attributes = array(
            /*  if (account_description is null)
                then (sort by client_surname, client_name1...), 
                else (sort by account_description) */
            'varFullname'=>array(
                'asc'=>"IFNULL(account_description,
                    CONCAT( IFNULL(client_surname,''),
                            IFNULL(client_name1,''),
                            IFNULL(client_name2,''),
                            IFNULL(client_name3,''))
                )",
                'desc'=>"IFNULL(account_description,
                    CONCAT( IFNULL(client_surname,''),
                            IFNULL(client_name1,''),
                            IFNULL(client_name2,''),
                            IFNULL(client_name3,''))
                ) desc",
            ),
            '*',
        );
 
        /* Default Sort Order*/
        $sort->defaultOrder= array(
            'varFullname'=>CSort::SORT_ASC,
        );
 
        return new CActiveDataProvider($this, array(
            'pagination'=>array('pageSize'=>20),
            'criteria'=>$criteria,
            'sort'=>$sort,
        ));
    }
 
}

array(
    'name'  => 'varFullname',
    'value' => '($data->CompiledFullname) ? $data->CompiledFullname : ""',
    'header'=> CHtml::encode($model->getAttributeLabel('account_description')),
    'filter'=> CHtml::activeTextField($model, 'varFullname'),
),

public $varColour;
 
public function getCompiledColour()
{
    if($this->type == 1)
    {
        return 'Red';
    }
    elseif($this->type == 2)
    {
        return 'Yellow';
    }
    else
    {
    return 'Green';
    }
}
 
array('varColour', 'safe', 'on'=>'search')
 
public function attributeLabels()
{
    return array(
        'varColour' => 'Colour',
    );
}
 
public function search()
{
    $criteria   = new CDbCriteria;
    $sort       = new CSort;
 
    /* Filter Criteria */
    $criteria->compare(
        "CASE t.type
            WHEN 1 THEN 'Red'
            WHEN 2 THEN 'Yellow'
            ELSE 'Green' 
        END", $this->varColour, true);
 
    /* Sort Criteria */
    $sort->attributes = array(
 
        'varColour'=>array(
            'asc'=>"
                CASE t.type
                    WHEN 1 THEN 'Red'
                    WHEN 2 THEN 'Yellow'
                    ELSE 'Green' 
                END",
            'desc'=>"
                CASE t.type
                    WHEN 1 THEN 'Red'
                    WHEN 2 THEN 'Yellow'
                    ELSE 'Green' 
                END desc",
        ),
 
        '*',
    );
 
    return new CActiveDataProvider($this, array(
        'pagination'=>array(
            'pageSize'=>20,
        ),
        'criteria'=>$criteria,
        'sort'=>$sort,
    ));
}

array(
    'name'=>'varColour',
    'value'=>'($data->CompiledColour) ? $data->CompiledColour : ""',
    'header'=> CHtml::encode($model->getAttributeLabel('varColour')),
    'filter' => CHtml::activeTextField($model, 'varColour'),
),