-- Code Here
select *
from transactions
where customer is not NULL;

-- Code here
select *
from transactions
where customer is NULL;

-- Code Here
select * 
from transactions
where customer like 'S%r'

-- Code Here
select *
from transactions
where store not in ('BIE Store Jakarta', 'BIE Store Bandung');

-- Code Here
select * 
from transactions
where store in ('BIE Store Bandung', 'BIE Store Palembang', 'BIE Store Malang');