Add OR Clause to addSearchCondition

$criteria->addSearchCondition('AuthAssignment.itemname', 'Staff');
$criteria->addSearchCondition('AuthAssignment.itemname', 'Waiter' , true , 'OR');
$criteria->addSearchCondition('AuthAssignment.itemname', 'Admin' , true , 'OR');
$criteria->addSearchCondition('AuthAssignment.itemname', 'Cashier' , true , 'OR'); 

Join two tables with CDbCriteria

$criteria=new CDbCriteria;
$criteria->alias = 'de';
$criteria->select = 'expences_type.type AS expences_type_name,de.id,de.driver_id,de.details,de.comment,de.price';
$criteria -> join = "inner join  expences_type on  expences_type.id = de.expences_type ";
$criteria->compare('id',$this->id);
$criteria->compare('driver_id',$this->driver_id);
$criteria->compare('expences_type',$this->expences_type);
$criteria->compare('details',$this->details,true);
$criteria->compare('comment',$this->comment,true);
$criteria->compare('price',$this->price,true);
$criteria->compare('request_date',$this->request_date,true);
$criteria->compare('paid_date',$this->paid_date,true);
$criteria->compare('update_date',$this->update_date,true);
$criteria->compare('update_by',$this->update_by);
$criteria->compare('create_date',$this->create_date,true);
$criteria->compare('create_by',$this->create_by);
$criteria->compare('expences_type.type',$this->expences_type_name);

return new CActiveDataProvider($this, array(
'criteria'=>$criteria,
));

Make Buttons Visible or Not visible according to permissions Given

<?php
$user_id=Yii::app()->user->id;
$AuthAssignments = AuthAssignment::model() -> findAll(array("condition"=>"userid = $user_id","order"=>"itemname"));

$Authitemchildren = Authitemchild::model() -> findAll();
$visibleView = 'false;';
$visibleEdit = 'false;';
$visibleDelete = 'false;';
foreach($Authitemchildren as $Authitemchild){
foreach($AuthAssignments as $AuthAssignment){
if($Authitemchild['parent']==$AuthAssignment['itemname'] && $Authitemchild['child']=='MainMenu.View'){
$visibleView = 'true;';
}else if($Authitemchild['parent']==$AuthAssignment['itemname'] && $Authitemchild['child']=='MainMenu.Update'){
$visibleEdit = 'true;';
}
else if($Authitemchild['parent']==$AuthAssignment['itemname'] && $Authitemchild['child']=='MainMenu.Delete'){
$visibleDelete = 'true;';
}
}
}

In buttons

array(

'class'=>'bootstrap.widgets.TbButtonColumn',

'template'=>'{View}{Edit}{Delete}',

'buttons'=>array

(

 

'View' => array

(

'label'=>'View',

'visible' => $visibleView,

'url'=>'Yii::app()->createUrl("MainMenu/view", array("id"=>$data->id))',

'imageUrl' => Yii::app()->baseUrl . '/images/icon/viewicon.jpg',

'options'=>array(

'style'=>'width:130px;height:130px;',

//   'class'=>'btn btn-small btn-info',

),

),

),),