Left join vs subquery [closed]

I have the following query with left join can I make this as subquery instead? Will it work faster since it’s the same table? I will only want to get the revenue rows and show revenue2 only for them

SELECT *
FROM
    (SELECT 
         s_campaign_id,
         SUM(CASE
                WHEN d_gen_date BETWEEN '2021-01-31' AND '2021-01-31'
                   THEN f_revenue
                   ELSE 0
             END) AS revenue,
         SUM(CASE
                WHEN d_gen_date BETWEEN '2021-01-30' AND '2021-01-30' 
                   THEN f_revenue
                   ELSE 0
             END) AS revenue2
     FROM 
         tbl_reports
     WHERE 
         (d_gen_date >= '2021-01-31'
          AND d_gen_date <= '2021-01-31')
     GROUP BY 
         s_campaign_id) d1
LEFT JOIN
    (SELECT 
         s_campaign_id,
         SUM(CASE
                WHEN d_gen_date BETWEEN '2021-01-30' AND '2021-01-30' 
                   THEN f_revenue
                   ELSE 0
             END) AS revenue2
     FROM 
         tbl_reports
     WHERE 
         (d_gen_date BETWEEN '2021-01-30' AND '2021-01-30')
     GROUP BY 
         s_campaign_id) d2 ON d1.s_campaign_id = d2.s_campaign_id

Answer

Your query is quite suspicious as you can achieve the desired result using minor changes in first query as follows:

  SELECT T.* FROM
  (SELECT s_campaign_id,
         SUM(CASE WHEN d_gen_date = '2021-01-31' THEN f_revenue ELSE 0 END) AS revenue,
         SUM(CASE WHEN d_gen_date = '2021-01-30' THEN f_revenue ELSE 0 END) AS revenue2 
    FROM tbl_reports 
   WHERE (d_gen_date>='2021-01-30' AND d_gen_date<='2021-01-31') 
   GROUP BY s_campaign_id) T
   WHERE EXISTS (select 1 from tbl_reports tt 
                  where t.s_campaign_id = tt.s_campaign_id
                    and tt.d_gen_date ='2021-01-31')