sql纵向，横向，去Null值，去0值求平均数

SELECT
	round( avg( nullif( temperature, 0 )), 2 ) temperature,
	sum( electricity_sum + electricity_1 + electricity_2 + electricity_3 ) AS electricity_sum,
	sum( power_sum ) AS power_sum,
	round((
		IF
			(
				avg(
				nullif( voltage_sum, 0 )) IS NULL,
				0,
				avg(
				nullif( voltage_sum, 0 )))+
		IF
			(
				avg(
				nullif( voltage_1, 0 )) IS NULL,
				0,
				avg(
				nullif( voltage_1, 0 )))+
		IF
			(
				avg(
				nullif( voltage_2, 0 )) IS NULL,
				0,
				avg(
				nullif( voltage_2, 0 )))+
		IF
			(
				avg(
				nullif( voltage_3, 0 )) IS NULL,
				0,
				avg(
				nullif( voltage_3, 0 ))))/(
		IF
			( avg( nullif( voltage_1, 0 )) = 0 OR avg( nullif( voltage_1, 0 )) IS NULL, 0, 1 )+
		IF
			( avg( nullif( voltage_2, 0 )) = 0 OR avg( nullif( voltage_2, 0 )) IS NULL, 0, 1 )+
		IF
			( avg( nullif( voltage_2, 0 )) = 0 OR avg( nullif( voltage_3, 0 )) IS NULL, 0, 1 )+
		IF
			( avg( nullif( voltage_sum, 0 )) = 0 OR avg( nullif( voltage_sum, 0 )) IS NULL, 0, 1 )),
		2 
	) AS voltage_sum 
FROM
	power 
WHERE
	room_id = 214