MysteryShopper_ReportRecord.php

<?php

namespace Craft;

class MysteryShopper_ReportRecord extends BaseRecord
{
    public function getTableName()
    {
        return 'mysteryshopper_Report';
    }

    protected function defineAttributes()
    {
        return array(
            'report'     => array(AttributeType::String, 'default' => '', 'column' => ColumnType::Text),
            'stage'     => array(AttributeType::Number),
            'author'     => array(AttributeType::Number),
            'shop'     => array(AttributeType::Number),
            'instance'     => array(AttributeType::Number),
            'event'     => array(AttributeType::Number),
            'status'     => array(AttributeType::String, 'default' => 'pending'),
        );
    }

    /**
     * @return array
     */
    public function defineRelations()
    {
        return array(
        );
    }
}

MysteryShopper_ReportService.php

<?php

namespace Craft;

class MysteryShopper_ReportService extends BaseApplicationComponent
{
    public function saveReport(MysteryShopper_ReportModel $model,$id = null)
    {
    	$pre = $model->report;
    	$id = (int)$id;
    	
    	if ($id > 0) {
			$tmp = [];
			$record = MysteryShopper_ReportRecord::model()->findById($id);
			$fields = json_decode($record->report);			
			// merge fields - new values take precedence
			$merge = (object) array_merge((array) $fields, (array) json_decode($model->report));
			$model->report = json_encode($merge);
			$record->setAttribute('report',json_encode($merge));
		} else {
			$record = new MysteryShopper_ReportRecord;
		}	
		foreach ($model AS $key => $value)
		{
			if ($value) $record->setAttribute($key,$value);
		}

		if ($record->save(false)) {
			MysteryShopperPlugin::Log('Report saved via service');
		} else {
			MysteryShopperPlugin::Log('Report failed to save via service');
		}
		return $record->id;
    }

}