前提是我的数据表字段时大写的。
如果$activity_data = $activity_model->field('appid,name,business_id')->where("activity_id='$acti_id'")->find();（lastsql:SELECT `appid`,`name`,`business_id` FROM `shakecard_activity` WHERE ( activity_id='1111' ) LIMIT 1）是执行where条件的，而如果$activity_data = $activity_model->field('appid,name,business_id')->where(array('activity_id'=>$acti_id))->find();（lastsql:SELECT `appid`,`name`,`business_id` FROM `shakecard_activity`）where条件不执行；这时必须要
$activity_data = $activity_model->field('appid,name,business_id')->where(array('ACTIVITY_ID'=>$acti_id))->find();（lastsql:SELECT `appid`,`name`,`business_id` FROM `shakecard_activity` WHERE ( activity_id='1111' ) LIMIT 1）where语句才使用，得出正确数据