删除重复数据

delete iot_instruction
from 
iot_instruction,
(
	SELECT
   min(id) id,
	 GROUP_CONCAT(id) as ids,
   command,
	 instruction_type,
	 protocol_id
  FROM
   iot_instruction
  GROUP BY
   command,instruction_type,protocol_id
  HAVING
   count(*) > 1
) t2
where iot_instruction.command = t2.command and iot_instruction.protocol_id = t2.protocol_id
and iot_instruction.instruction_type= t2.instruction_type and iot_instruction.id>t2.id;