Anda boleh menggunakan subkueri untuk mengagregat jadual churn dan upsell.

Seperti yang ditunjukkan di bawah:

select d.Closing_date,
       sum(d.Revenue_won) as 'Revenue gained from new deals', 
       c.`Revenue lost from churn`,
       u.`Revenue gained from upsell`
from deals d
inner join ( select Closing_date,
                    sum(Revenue_lost) as 'Revenue lost from churn'
            from churns 
            group by Closing_date 
            ) as c on c.Closing_date=d.Closing_date
inner join ( select Closing_date,
                    sum(Revenue_won) as 'Revenue gained from upsell'
             from upsells u 
             group by Closing_date 
             ) as u on  u.Closing_date=d.Closing_date          
group by d.Closing_date ;

https://dbfiddle.uk/?rdbms=mysql_8.0&fiddle=0875563c9ab7f9385711dde21cd98b47 一个>

Tolong jangan simpan tarikh sebagai teks, anda akan menghadapi banyak kesukaran. Kalau nak format tarikh boleh guna DATE_FORMAT

Perhatian. Jika tarikh lain wujud dalam jadual transaksi tetapi tidak dalam dua jadual lain, tarikh itu akan ditapis keluar daripada keputusan. Jika anda mahu, gunakan LEFT JOIN而不是INNER JOIN.

**Edit

select d.Closing_date,
       d.`Revenue gained from new deals`,
       c.`Revenue lost from churn`,
       u.`Revenue gained from upsell`
from  ( select Closing_date,
               sum(Revenue_won) as 'Revenue gained from new deals'
        from deals 
        group by Closing_date ) as d 
inner join ( select Closing_date,
                    sum(Revenue_lost) as 'Revenue lost from churn'
            from churns 
            group by Closing_date 
            ) as c on c.Closing_date=d.Closing_date
inner join ( select Closing_date,
                    sum(Revenue_won) as 'Revenue gained from upsell'
             from upsells u 
             group by Closing_date 
             ) as u on  u.Closing_date=d.Closing_date           ;

https://dbfiddle.uk/S61QeLBX