MySQL 8.0

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CREATE tABLE bookings (id int,price DECIMAL(8,2),loyaltypoints int)
INSERT INTO bookings VALUES (214,12.12,1)
CREATE TABLE paymentitems (bookingid int,itemamount int)
INSERT INTO paymentitems VALUES (214,10.11),(214,2.01)
select MIN(b.price),sum(ifnull(i.itemamount,0)) totalpaid,SUM(b.loyaltypoints)
from bookings b 
    left join paymentitems i on i.bookingid = b.id
where b.id = 214


MIN(b.price)
totalpaid
SUM(b.loyaltypoints)


12.12
12
2