framework/data/BaseDataProvider.php
public function refresh()
    {
        $this->_totalCount = null;
        $this->_models = null;
        $this->_keys = null;
    }
public function refresh()
    {
        $this->_totalCount = null;
        $this->_models = null;
        $this->_keys = null;
    }
Refreshes the data provider.
After calling this method, if [[getModels()]], [[getKeys()]] or [[getTotalCount()]] is called again,
they will re-execute the query and return the latest data available.