mysql自動計數

set @data_date := null;
set @num := 1;
SET @activity_name :=null;
set @num1 := 1;
SELECT   data_date,
activity_name,activity_pay_amount,
if(@data_date IS null or @data_date <> data_date, @num :=1,@num :=@num+1) ct,
if(@activity_name IS null or @activity_name <> activity_name, @num1 :=1,@num1 :=@num1+1) ct1,
@data_date := data_date,
@activity_name := activity_name
FROM aaaaaaaaaaaaa
ORDER BY data_date