SELECT Carrier, SUM(Memory_in_G) FROM phone GROUP BY Carrier
A bar chart about what are the memories and carriers of phones?
CREATE TABLE phone_market (
    Market_ID int,
    Phone_ID text,
    Num_of_stock int
)

CREATE TABLE market (
    Market_ID int,
    District text,
    Num_of_employees int,
    Num_of_shops real,
    Ranking int
)

CREATE TABLE phone (
    Name text,
    Phone_ID int,
    Memory_in_G int,
    Carrier text,
    Price real
)