你还是先子查询一下,看看数据有值木有:SELECT * from els_device_alarm_info e WHERE e.device_id in ( SELECT els_d.device_id d_id from car_info c_info,driver_info d,els_system_params els_param,els_device els_d WHERE els_param.param_type = 'region_code' AND els_param.param_value = c_info.region_code AND els_d.car_id = c_info.id AND d.driver_id = c_info.driver_id )
tmp.id ,
tmp.lic_num ,
tmp.driver_name ,
tmp.param_name ,
e.alarm_type ,
e.alarm_name
我去试试看连数据都没了,在mysql里很正常,我这sql是不是写的有问题呢?
WHERE e.device_id in (
SELECT els_d.device_id d_id
from car_info c_info,driver_info d,els_system_params els_param,els_device els_d
WHERE
els_param.param_type = 'region_code'
AND
els_param.param_value = c_info.region_code
AND
els_d.car_id = c_info.id
AND
d.driver_id = c_info.driver_id
)